Block #58,926

1CCLength 8★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/17/2013, 11:22:41 PM · Difficulty 8.9624 · 6,730,833 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
b88db0b409cb91d750c633d16ddaf6f8584f2a8ca45e9a77661d58517752afe7

Height

#58,926

Difficulty

8.962429

Transactions

2

Size

430 B

Version

2

Bits

08f661bb

Nonce

509

Timestamp

7/17/2013, 11:22:41 PM

Confirmations

6,730,833

Merkle Root

7901a4f8c401163290121f8fd76ae5652d26686176105d31985be94b6ce3fbad
Transactions (2)
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.

2.820 × 10¹⁰³(104-digit number)
28200015508631992533…55860942021673386319
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
2.820 × 10¹⁰³(104-digit number)
28200015508631992533…55860942021673386319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.640 × 10¹⁰³(104-digit number)
56400031017263985066…11721884043346772639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.128 × 10¹⁰⁴(105-digit number)
11280006203452797013…23443768086693545279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.256 × 10¹⁰⁴(105-digit number)
22560012406905594026…46887536173387090559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.512 × 10¹⁰⁴(105-digit number)
45120024813811188053…93775072346774181119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.024 × 10¹⁰⁴(105-digit number)
90240049627622376106…87550144693548362239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.804 × 10¹⁰⁵(106-digit number)
18048009925524475221…75100289387096724479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.609 × 10¹⁰⁵(106-digit number)
36096019851048950442…50200578774193448959
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 8 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
CommonChain length 8

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,562,039 XPM·at block #6,789,758 · updates every 60s