Block #414,231

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/21/2014, 8:08:19 PM · Difficulty 10.4086 · 6,380,426 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
a86e024147896299b7fbe9ac7f44ad791e9afb22ffbc4e5f764b7dd2ac032796

Height

#414,231

Difficulty

10.408585

Transactions

2

Size

4.17 KB

Version

2

Bits

0a68990c

Nonce

317,737

Timestamp

2/21/2014, 8:08:19 PM

Confirmations

6,380,426

Merkle Root

fd2134b2246f94559e01faf30a5631100e68370475ab8489e19b1cf9714f1143
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.

1.850 × 10⁹⁶(97-digit number)
18509760946742585499…47191357615296058819
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
1.850 × 10⁹⁶(97-digit number)
18509760946742585499…47191357615296058819
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.701 × 10⁹⁶(97-digit number)
37019521893485170999…94382715230592117639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.403 × 10⁹⁶(97-digit number)
74039043786970341998…88765430461184235279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.480 × 10⁹⁷(98-digit number)
14807808757394068399…77530860922368470559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.961 × 10⁹⁷(98-digit number)
29615617514788136799…55061721844736941119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.923 × 10⁹⁷(98-digit number)
59231235029576273598…10123443689473882239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.184 × 10⁹⁸(99-digit number)
11846247005915254719…20246887378947764479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.369 × 10⁹⁸(99-digit number)
23692494011830509439…40493774757895528959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.738 × 10⁹⁸(99-digit number)
47384988023661018879…80987549515791057919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.476 × 10⁹⁸(99-digit number)
94769976047322037758…61975099031582115839
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:57,601,306 XPM·at block #6,794,656 · updates every 60s
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