Block #32,279

1CCLength 7★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/14/2013, 2:19:01 AM · Difficulty 7.9901 · 6,759,139 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
f04a8590550e8a9d77e14a39fc411ec08d3053f59a82041c7933ad432c975d06

Height

#32,279

Difficulty

7.990118

Transactions

2

Size

577 B

Version

2

Bits

07fd785e

Nonce

232

Timestamp

7/14/2013, 2:19:01 AM

Confirmations

6,759,139

Merkle Root

bf3e89fb48fa090ba7701548b9dfa9d94982277809aeba88f7a010b1fbb464f1
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.

1.197 × 10¹⁰⁷(108-digit number)
11972190791296239281…30030993719123150559
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
1.197 × 10¹⁰⁷(108-digit number)
11972190791296239281…30030993719123150559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.394 × 10¹⁰⁷(108-digit number)
23944381582592478563…60061987438246301119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.788 × 10¹⁰⁷(108-digit number)
47888763165184957127…20123974876492602239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.577 × 10¹⁰⁷(108-digit number)
95777526330369914255…40247949752985204479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.915 × 10¹⁰⁸(109-digit number)
19155505266073982851…80495899505970408959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.831 × 10¹⁰⁸(109-digit number)
38311010532147965702…60991799011940817919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.662 × 10¹⁰⁸(109-digit number)
76622021064295931404…21983598023881635839
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 7 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 7

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:57,575,281 XPM·at block #6,791,417 · updates every 60s
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