Block #337,030

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/31/2013, 9:25:51 AM · Difficulty 10.1383 · 6,464,303 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a841a7c84acbd77db3dd41db261220bb2780fc3352d053481f317127de6124d7

Height

#337,030

Difficulty

10.138282

Transactions

8

Size

4.05 KB

Version

2

Bits

0a23666c

Nonce

37,225

Timestamp

12/31/2013, 9:25:51 AM

Confirmations

6,464,303

Merkle Root

77c65929a43215fe0a4c09b7170db22009ea83b598197c6ba5f503b14a6a5d31
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.

9.971 × 10⁹⁵(96-digit number)
99715580639180820560…81338819223392238319
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
9.971 × 10⁹⁵(96-digit number)
99715580639180820560…81338819223392238319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.994 × 10⁹⁶(97-digit number)
19943116127836164112…62677638446784476639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.988 × 10⁹⁶(97-digit number)
39886232255672328224…25355276893568953279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.977 × 10⁹⁶(97-digit number)
79772464511344656448…50710553787137906559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.595 × 10⁹⁷(98-digit number)
15954492902268931289…01421107574275813119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.190 × 10⁹⁷(98-digit number)
31908985804537862579…02842215148551626239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.381 × 10⁹⁷(98-digit number)
63817971609075725158…05684430297103252479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.276 × 10⁹⁸(99-digit number)
12763594321815145031…11368860594206504959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.552 × 10⁹⁸(99-digit number)
25527188643630290063…22737721188413009919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.105 × 10⁹⁸(99-digit number)
51054377287260580127…45475442376826019839
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:57,654,733 XPM·at block #6,801,332 · updates every 60s
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