Block #423,933

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 2/28/2014, 7:14:52 PM · Difficulty 10.3750 · 6,381,856 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
aa1dc07e379c4db4a49448aa51f4db6b4f515dd5088d021537a1cd0ea609e732

Height

#423,933

Difficulty

10.374995

Transactions

45

Size

11.45 KB

Version

2

Bits

0a5fffb2

Nonce

81,985

Timestamp

2/28/2014, 7:14:52 PM

Confirmations

6,381,856

Merkle Root

d7ec282797239dfcd31c22546bdf9cbf1eb8e7af49b6ad07610ae42f12b5c06c
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.

5.970 × 10⁹⁷(98-digit number)
59702745794051641565…08651190491099343999
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
5.970 × 10⁹⁷(98-digit number)
59702745794051641565…08651190491099343999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.194 × 10⁹⁸(99-digit number)
11940549158810328313…17302380982198687999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.388 × 10⁹⁸(99-digit number)
23881098317620656626…34604761964397375999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.776 × 10⁹⁸(99-digit number)
47762196635241313252…69209523928794751999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
9.552 × 10⁹⁸(99-digit number)
95524393270482626505…38419047857589503999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.910 × 10⁹⁹(100-digit number)
19104878654096525301…76838095715179007999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.820 × 10⁹⁹(100-digit number)
38209757308193050602…53676191430358015999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
7.641 × 10⁹⁹(100-digit number)
76419514616386101204…07352382860716031999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.528 × 10¹⁰⁰(101-digit number)
15283902923277220240…14704765721432063999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.056 × 10¹⁰⁰(101-digit number)
30567805846554440481…29409531442864127999
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:57,690,400 XPM·at block #6,805,788 · updates every 60s
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