Block #360,392

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/15/2014, 10:35:12 AM · Difficulty 10.3907 · 6,435,701 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
34bab985930f4c277eaa116267970bd773ef1d67cc7cdfb82c139ab6dbf4687f

Height

#360,392

Difficulty

10.390724

Transactions

5

Size

1.52 KB

Version

2

Bits

0a640677

Nonce

18,665

Timestamp

1/15/2014, 10:35:12 AM

Confirmations

6,435,701

Merkle Root

6aded36e0a4f61d0a28749542d621c15caec602b30d004801f0b0548d42c403d
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.

4.219 × 10⁹³(94-digit number)
42192200971974821874…92298262483991156089
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
4.219 × 10⁹³(94-digit number)
42192200971974821874…92298262483991156089
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.438 × 10⁹³(94-digit number)
84384401943949643748…84596524967982312179
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.687 × 10⁹⁴(95-digit number)
16876880388789928749…69193049935964624359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.375 × 10⁹⁴(95-digit number)
33753760777579857499…38386099871929248719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.750 × 10⁹⁴(95-digit number)
67507521555159714998…76772199743858497439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.350 × 10⁹⁵(96-digit number)
13501504311031942999…53544399487716994879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.700 × 10⁹⁵(96-digit number)
27003008622063885999…07088798975433989759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.400 × 10⁹⁵(96-digit number)
54006017244127771998…14177597950867979519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.080 × 10⁹⁶(97-digit number)
10801203448825554399…28355195901735959039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.160 × 10⁹⁶(97-digit number)
21602406897651108799…56710391803471918079
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:57,612,743 XPM·at block #6,796,092 · updates every 60s
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