Block #159,652

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 9/11/2013, 7:19:59 AM · Difficulty 9.8643 · 6,639,669 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
06e6d6073549b9adcb60f7f11d7ff181c61549eae824923490e999c1c395a7a7

Height

#159,652

Difficulty

9.864295

Transactions

8

Size

3.90 KB

Version

2

Bits

09dd426f

Nonce

33,073

Timestamp

9/11/2013, 7:19:59 AM

Confirmations

6,639,669

Merkle Root

4263c92f7e84520f6c84dab355e2a4d103873ddbc8bed0295ddd75475c08027b
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.

6.992 × 10⁹²(93-digit number)
69928433866360222961…01556826460136976799
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
6.992 × 10⁹²(93-digit number)
69928433866360222961…01556826460136976799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.398 × 10⁹³(94-digit number)
13985686773272044592…03113652920273953599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.797 × 10⁹³(94-digit number)
27971373546544089184…06227305840547907199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.594 × 10⁹³(94-digit number)
55942747093088178368…12454611681095814399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.118 × 10⁹⁴(95-digit number)
11188549418617635673…24909223362191628799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.237 × 10⁹⁴(95-digit number)
22377098837235271347…49818446724383257599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.475 × 10⁹⁴(95-digit number)
44754197674470542695…99636893448766515199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
8.950 × 10⁹⁴(95-digit number)
89508395348941085390…99273786897533030399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.790 × 10⁹⁵(96-digit number)
17901679069788217078…98547573795066060799
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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 9

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:57,638,616 XPM·at block #6,799,320 · updates every 60s
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