Home/Chain Registry/Block #316,397

Block #316,397

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/17/2013, 1:23:27 AM · Difficulty 10.1336 · 6,479,604 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
aa4ee52355bdedd47f79007eadca9c0a8b0979bcdff2df9133a6f564a2c57d47

Height

#316,397

Difficulty

10.133637

Transactions

6

Size

1.26 KB

Version

2

Bits

0a223604

Nonce

59,453

Timestamp

12/17/2013, 1:23:27 AM

Confirmations

6,479,604

Merkle Root

71fd657b547bf0d933e4ec42bd1aedc2e6109f4ff757393caff30aad206b3228
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

3.334 × 10⁹⁵(96-digit number)
33349587974446275335…18012060379308474320
Discovered Prime Numbers
p_k = 2^k × origin − 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

1
origin − 1
3.334 × 10⁹⁵(96-digit number)
33349587974446275335…18012060379308474319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.669 × 10⁹⁵(96-digit number)
66699175948892550670…36024120758616948639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.333 × 10⁹⁶(97-digit number)
13339835189778510134…72048241517233897279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.667 × 10⁹⁶(97-digit number)
26679670379557020268…44096483034467794559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.335 × 10⁹⁶(97-digit number)
53359340759114040536…88192966068935589119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.067 × 10⁹⁷(98-digit number)
10671868151822808107…76385932137871178239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.134 × 10⁹⁷(98-digit number)
21343736303645616214…52771864275742356479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.268 × 10⁹⁷(98-digit number)
42687472607291232428…05543728551484712959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.537 × 10⁹⁷(98-digit number)
85374945214582464857…11087457102969425919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.707 × 10⁹⁸(99-digit number)
17074989042916492971…22174914205938851839
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Cunningham Chain of the First Kind. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

View full Prime Chain Discovery page →
★★☆☆☆
Rarity
UncommonChain length 10
How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 316397

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock aa4ee52355bdedd47f79007eadca9c0a8b0979bcdff2df9133a6f564a2c57d47

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #316,397 on Chainz ↗
Circulating Supply:57,612,096 XPM·at block #6,796,000 · updates every 60s
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