Block #316,934

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/17/2013, 8:54:46 AM · Difficulty 10.1482 · 6,488,002 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b50e59b175b91f8de76ce9edebfa34a19c1685f1a257ae55828d8fe39e4608c7

Height

#316,934

Difficulty

10.148175

Transactions

3

Size

766 B

Version

2

Bits

0a25eec9

Nonce

11,698

Timestamp

12/17/2013, 8:54:46 AM

Confirmations

6,488,002

Merkle Root

bf3e928fe47378ae26b829356ff499a0090c699f0fe1e6f1e502310038050c4d
Transactions (3)
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.

1.144 × 10⁹⁴(95-digit number)
11440420975378530798…38961318241859867759
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
1.144 × 10⁹⁴(95-digit number)
11440420975378530798…38961318241859867759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.288 × 10⁹⁴(95-digit number)
22880841950757061596…77922636483719735519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.576 × 10⁹⁴(95-digit number)
45761683901514123193…55845272967439471039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.152 × 10⁹⁴(95-digit number)
91523367803028246386…11690545934878942079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.830 × 10⁹⁵(96-digit number)
18304673560605649277…23381091869757884159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.660 × 10⁹⁵(96-digit number)
36609347121211298554…46762183739515768319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.321 × 10⁹⁵(96-digit number)
73218694242422597109…93524367479031536639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.464 × 10⁹⁶(97-digit number)
14643738848484519421…87048734958063073279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.928 × 10⁹⁶(97-digit number)
29287477696969038843…74097469916126146559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.857 × 10⁹⁶(97-digit number)
58574955393938077687…48194939832252293119
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:57,683,562 XPM·at block #6,804,935 · updates every 60s
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