Block #360,750

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/15/2014, 3:28:04 PM · Difficulty 10.3986 · 6,432,013 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e1b9811f50e067fcf7c7eb20be663094435a6df28c8da65c764fc2f4a4483de7

Height

#360,750

Difficulty

10.398590

Transactions

3

Size

1.71 KB

Version

2

Bits

0a660a03

Nonce

101,672

Timestamp

1/15/2014, 3:28:04 PM

Confirmations

6,432,013

Merkle Root

0d16d042467f3ce3ea4c2cd25efd23cd83488d47a7ceb99b9ad60321a7926200
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.

1.511 × 10⁹⁶(97-digit number)
15114100662363816584…27058122876811232959
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
1.511 × 10⁹⁶(97-digit number)
15114100662363816584…27058122876811232959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.022 × 10⁹⁶(97-digit number)
30228201324727633168…54116245753622465919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.045 × 10⁹⁶(97-digit number)
60456402649455266337…08232491507244931839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.209 × 10⁹⁷(98-digit number)
12091280529891053267…16464983014489863679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.418 × 10⁹⁷(98-digit number)
24182561059782106534…32929966028979727359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.836 × 10⁹⁷(98-digit number)
48365122119564213069…65859932057959454719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.673 × 10⁹⁷(98-digit number)
96730244239128426139…31719864115918909439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.934 × 10⁹⁸(99-digit number)
19346048847825685227…63439728231837818879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.869 × 10⁹⁸(99-digit number)
38692097695651370455…26879456463675637759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.738 × 10⁹⁸(99-digit number)
77384195391302740911…53758912927351275519
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:57,586,083 XPM·at block #6,792,762 · updates every 60s
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