Block #324,935

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/22/2013, 4:34:08 PM · Difficulty 10.2066 · 6,471,432 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b41215473b3cdacd50ed830fb445a92bc51793419749268200cf530986114816

Height

#324,935

Difficulty

10.206609

Transactions

5

Size

1.08 KB

Version

2

Bits

0a34e44c

Nonce

118,786

Timestamp

12/22/2013, 4:34:08 PM

Confirmations

6,471,432

Merkle Root

aa07afdcaa4af2108ddf37641a1ba95d19b2762bffece9697098baeea7135362
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.

2.911 × 10¹⁰¹(102-digit number)
29116291622815440413…76946605140805999479
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
2.911 × 10¹⁰¹(102-digit number)
29116291622815440413…76946605140805999479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.823 × 10¹⁰¹(102-digit number)
58232583245630880826…53893210281611998959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.164 × 10¹⁰²(103-digit number)
11646516649126176165…07786420563223997919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.329 × 10¹⁰²(103-digit number)
23293033298252352330…15572841126447995839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.658 × 10¹⁰²(103-digit number)
46586066596504704661…31145682252895991679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.317 × 10¹⁰²(103-digit number)
93172133193009409322…62291364505791983359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.863 × 10¹⁰³(104-digit number)
18634426638601881864…24582729011583966719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.726 × 10¹⁰³(104-digit number)
37268853277203763728…49165458023167933439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.453 × 10¹⁰³(104-digit number)
74537706554407527457…98330916046335866879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.490 × 10¹⁰⁴(105-digit number)
14907541310881505491…96661832092671733759
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:57,614,930 XPM·at block #6,796,366 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.