Block #337,080

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/31/2013, 10:11:53 AM · Difficulty 10.1397 · 6,457,252 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c0ce0b4829ec3022f528e4265aa83c90ed8b905c0bfece0d929c7880ba76cb1b

Height

#337,080

Difficulty

10.139657

Transactions

5

Size

1.08 KB

Version

2

Bits

0a23c089

Nonce

162,947

Timestamp

12/31/2013, 10:11:53 AM

Confirmations

6,457,252

Merkle Root

282418435d9e5ff78ed2b666cc7d85ad4ba0b309b372ecf54ef97f667999004b
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.

9.862 × 10⁹⁹(100-digit number)
98624910131965987966…95282761858824984519
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
9.862 × 10⁹⁹(100-digit number)
98624910131965987966…95282761858824984519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.972 × 10¹⁰⁰(101-digit number)
19724982026393197593…90565523717649969039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.944 × 10¹⁰⁰(101-digit number)
39449964052786395186…81131047435299938079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.889 × 10¹⁰⁰(101-digit number)
78899928105572790373…62262094870599876159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.577 × 10¹⁰¹(102-digit number)
15779985621114558074…24524189741199752319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.155 × 10¹⁰¹(102-digit number)
31559971242229116149…49048379482399504639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.311 × 10¹⁰¹(102-digit number)
63119942484458232298…98096758964799009279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.262 × 10¹⁰²(103-digit number)
12623988496891646459…96193517929598018559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.524 × 10¹⁰²(103-digit number)
25247976993783292919…92387035859196037119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
5.049 × 10¹⁰²(103-digit number)
50495953987566585838…84774071718392074239
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:57,598,688 XPM·at block #6,794,331 · updates every 60s
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