Block #447,570

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/17/2014, 9:06:33 AM · Difficulty 10.3576 · 6,356,750 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
bf3d839a6630d71f85920ab4bfb38619419448fd9ce952fc8b86bc0ac50f1640

Height

#447,570

Difficulty

10.357608

Transactions

2

Size

2.13 KB

Version

2

Bits

0a5b8c38

Nonce

2,835,201

Timestamp

3/17/2014, 9:06:33 AM

Confirmations

6,356,750

Merkle Root

ffb9009e9a665c5a996bda89b81348f3c537ebfde6bb3b4759f48797a0821ab7
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.

3.376 × 10⁹⁵(96-digit number)
33767223908110473221…15638677304281061119
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
3.376 × 10⁹⁵(96-digit number)
33767223908110473221…15638677304281061119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.753 × 10⁹⁵(96-digit number)
67534447816220946442…31277354608562122239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.350 × 10⁹⁶(97-digit number)
13506889563244189288…62554709217124244479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.701 × 10⁹⁶(97-digit number)
27013779126488378577…25109418434248488959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.402 × 10⁹⁶(97-digit number)
54027558252976757154…50218836868496977919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.080 × 10⁹⁷(98-digit number)
10805511650595351430…00437673736993955839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.161 × 10⁹⁷(98-digit number)
21611023301190702861…00875347473987911679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.322 × 10⁹⁷(98-digit number)
43222046602381405723…01750694947975823359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.644 × 10⁹⁷(98-digit number)
86444093204762811446…03501389895951646719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.728 × 10⁹⁸(99-digit number)
17288818640952562289…07002779791903293439
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:57,678,614 XPM·at block #6,804,319 · updates every 60s
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