Block #344,917

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/5/2014, 2:33:01 PM · Difficulty 10.2037 · 6,461,251 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b160a6c61957983187489f385f8ca48cd1c9051f8a09da31e7a3a9da21da3735

Height

#344,917

Difficulty

10.203724

Transactions

21

Size

27.56 KB

Version

2

Bits

0a342744

Nonce

77,775

Timestamp

1/5/2014, 2:33:01 PM

Confirmations

6,461,251

Merkle Root

6b74e43509554d5cc7740e7297641d349879b1db55e6baf55a95931a6901a10f
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.

1.170 × 10⁹⁴(95-digit number)
11706231100689978504…47494326574024844799
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
1.170 × 10⁹⁴(95-digit number)
11706231100689978504…47494326574024844799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.341 × 10⁹⁴(95-digit number)
23412462201379957008…94988653148049689599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.682 × 10⁹⁴(95-digit number)
46824924402759914016…89977306296099379199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.364 × 10⁹⁴(95-digit number)
93649848805519828032…79954612592198758399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.872 × 10⁹⁵(96-digit number)
18729969761103965606…59909225184397516799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.745 × 10⁹⁵(96-digit number)
37459939522207931212…19818450368795033599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.491 × 10⁹⁵(96-digit number)
74919879044415862425…39636900737590067199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.498 × 10⁹⁶(97-digit number)
14983975808883172485…79273801475180134399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.996 × 10⁹⁶(97-digit number)
29967951617766344970…58547602950360268799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.993 × 10⁹⁶(97-digit number)
59935903235532689940…17095205900720537599
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:57,693,426 XPM·at block #6,806,167 · updates every 60s
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