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set "GOPATH=C:\g\ethereum\go-ethereum-src"
set "Path=%USERPROFILE%\bin;%Path%"
setx GOPATH "%GOPATH%"
setx Path "%Path%"
mkdir src\github.com\ethereum
git clone https://github.com/ethereum/go-ethereum src\github.com\ethereum\go-ethereum
cd src\github.com\ethereum\go-ethereum
go get -u -v golang.org/x/net/context

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@ericmaino this is how to install Node 6 or 7 on Ubuntu, via PPA

`curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -`
`curl -sL https://deb.nodesource.com/setup_7.x | sudo -E bash -`

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// provenance concept contract created by M.ElBoudi, A.Blackwell, M.Terzi et al during Ethereum development workshop in London

contract Certifiers {
        mapping (address => bool) certifier;
        address provenance;
        
        //initialiser is run the first time the contract is uploaded to the network. Launched by Provenance and reads provenance "public key"
        function Certifiers () {
            provenance = msg.sender;    
        }

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Genesis block Explanation

mixhash A 256-bit hash which proves, combined with the nonce, that a sufficient amount of computation has been carried out on this block: the Proof-of-Work (PoW). The combination of nonce and mixhash must satisfy a mathematical condition described in the Yellowpaper, 4.3.4. Block Header Validity, (44). It allows to verify that the Block has really been cryptographically mined, thus, from this aspect, is valid.

nonce A 64-bit hash, which proves, combined with the mix-hash, that a sufficient amount of computation has been carried out on this block: the Proof-of-Work (PoW). The combination of nonce and mixhash must satisfy a mathematical condition described in the Yellowpaper, 4.3.4. Block Header Validity, (44), and allows to verify that the Block has really been cryptographically mined and thus, from this aspect, is valid. The nonce is the cryptographically secure mining proof-of-work that proves beyond reasonable doubt that a particular amount of computation has been expended

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Skip to contentCrypto Posts https://rajbhadra.wordpress.com/2016/09/26/blockchain-based-letter-of-credit-implementation/ Home About Contact Blockchain based Letter of Credit implementation Posted on September 26, 2016 by rajbhadra Alice lives in America has an animal husbandry farm. Her farm has developed a cattle breed with advantageous properties. She is keen on selling them and lets people know of her desire.

Bob hears extremely positive reviews of Alice’s endeavor from his American peers and decides to purchase a bunch her cattle to fulfill the needs of his Belgian farm.

He requests Alice for a large order and they reach an agreement. Alice will ship the goods through Charlie the Carrier. Alice wants the funds to be delivered in Bank of Alice and Bob will utilize Bank of Bob. Alice does not trust Bob and being a canny businesswoman requests a Letter of Credit.

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// Ethereum + Solidity
// This code sample & more @ dev.oraclize.it

import "github.com/oraclize/ethereum-api/oraclizeAPI.sol";

contract PriceFeed is usingOraclize {
  uint public ETHUSD;
    
  function PriceFeed(){
    oraclize_setProof(proofType_TLSNotary | proofStorage_IPFS);

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const fs = require('fs');
const solc = require('solc');
const Web3 = require('web3');

// Connect to local Ethereum node
const web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));

// Compile the source code
const input = fs.readFileSync('Token.sol');
const output = solc.compile(input.toString(), 1);

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const fs = require('fs');
const solc = require('solc');
const Web3 = require('web3');
const Tx = require('ethereumjs-tx')

// Private key to use to sign the transactions
// To decrypt your private key, use e.g. https://www.myetherwallet.com/#view-wallet-info
// You will find your private key file in e.g. .ethereum/keystore or .parity/keys
// In this example the key should correspond to the web3.eth.coinbase address
var privateKey = new Buffer('088c110b6861b6c6c57461370d661301b29a7570d59cb83c6b4f19ec4b47f642', 'hex')

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var bip39 = require("bip39");
var ethwallet = require('ethereumjs-wallet');
var ProviderEngine = require("web3-provider-engine");
var WalletSubprovider = require('web3-provider-engine/subproviders/wallet.js');
var Web3Subprovider = require("web3-provider-engine/subproviders/web3.js");
var Web3 = require("web3");

// Insert raw hex private key here, e.g. using MyEtherWallet
var wallet = ethwallet.fromPrivateKey(Buffer.from('324a58ceac32c9a5a465a57a87600c086df72aa4ae0c6beb062436a2b6c0a2a6', 'hex'));

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var state = {
          imageifyIdenticons: false,
          txData: {
            "id":1467868023090690,"txParams":{"data":"0xa9059cbb0000000000000000000000008deb4d106090c3eb8f1950f727e87c4f884fb06f0000000000000000000000000000000000000000000000000000000000000064","from":"0xfdea65c8e26263f6d9a1b5de9555d2931a33b825","value":"0x16345785d8a0000","to":"0xbeb0ed3034c4155f3d16a64a5c5e7c8d4ea9e9c9","origin":"MetaMask","metamaskId":1467868023090690,"metamaskNetworkId":"2"},"time":1467868023090,"status":"unconfirmed","containsDelegateCall":false
          },
          accounts: {
            '0xfdea65c8e26263f6d9a1b5de9555d2931a33b825': {
              balance: "0x15e578bd8e9c8000",
            }
          },