Block #457,269

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/23/2014, 6:48:02 PM · Difficulty 10.4216 · 6,337,759 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
4f55ec83cc5cf9b3acfeb339b8fa4ae8eecb54550ec1486a33efd3d746a251f4

Height

#457,269

Difficulty

10.421603

Transactions

7

Size

2.63 KB

Version

2

Bits

0a6bee2e

Nonce

10,251

Timestamp

3/23/2014, 6:48:02 PM

Confirmations

6,337,759

Merkle Root

a622521fe7909a3696260e4fa3baf6262ccd5ac71557f25cf2a80ad8a8e45c79
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.

1.025 × 10⁹⁹(100-digit number)
10255110460356959114…05695628225757489919
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
1.025 × 10⁹⁹(100-digit number)
10255110460356959114…05695628225757489919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.051 × 10⁹⁹(100-digit number)
20510220920713918229…11391256451514979839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.102 × 10⁹⁹(100-digit number)
41020441841427836459…22782512903029959679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
8.204 × 10⁹⁹(100-digit number)
82040883682855672918…45565025806059919359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.640 × 10¹⁰⁰(101-digit number)
16408176736571134583…91130051612119838719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.281 × 10¹⁰⁰(101-digit number)
32816353473142269167…82260103224239677439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.563 × 10¹⁰⁰(101-digit number)
65632706946284538334…64520206448479354879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.312 × 10¹⁰¹(102-digit number)
13126541389256907666…29040412896958709759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.625 × 10¹⁰¹(102-digit number)
26253082778513815333…58080825793917419519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.250 × 10¹⁰¹(102-digit number)
52506165557027630667…16161651587834839039
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.

★★☆☆☆
Rarity
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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, …
Circulating Supply:57,604,264 XPM·at block #6,795,027 · updates every 60s
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