Block #429,202

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/4/2014, 3:01:00 PM · Difficulty 10.3471 · 6,368,676 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a3103e7c32d7c7e629651072d74a4b115c3346bcb02291ee0831aea7a89413ad

Height

#429,202

Difficulty

10.347145

Transactions

2

Size

514 B

Version

2

Bits

0a58de80

Nonce

51,013

Timestamp

3/4/2014, 3:01:00 PM

Confirmations

6,368,676

Merkle Root

1d84dc913a206682f0de37a92948c34c688be15a272ad3d03c76c0bbdb6bc077
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.

1.238 × 10⁹⁴(95-digit number)
12381107457047528280…04561700627647634559
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
1.238 × 10⁹⁴(95-digit number)
12381107457047528280…04561700627647634559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.476 × 10⁹⁴(95-digit number)
24762214914095056560…09123401255295269119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.952 × 10⁹⁴(95-digit number)
49524429828190113121…18246802510590538239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.904 × 10⁹⁴(95-digit number)
99048859656380226243…36493605021181076479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.980 × 10⁹⁵(96-digit number)
19809771931276045248…72987210042362152959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.961 × 10⁹⁵(96-digit number)
39619543862552090497…45974420084724305919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.923 × 10⁹⁵(96-digit number)
79239087725104180994…91948840169448611839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.584 × 10⁹⁶(97-digit number)
15847817545020836198…83897680338897223679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.169 × 10⁹⁶(97-digit number)
31695635090041672397…67795360677794447359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.339 × 10⁹⁶(97-digit number)
63391270180083344795…35590721355588894719
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:57,627,013 XPM·at block #6,797,877 · updates every 60s
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