Block #146,088

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 9/2/2013, 6:59:41 AM · Difficulty 9.8470 · 6,657,355 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
2231a93b0e1c62a8aafc6883c21743cc7e361759c9a4bbf8443bc3c354964e6f

Height

#146,088

Difficulty

9.847001

Transactions

5

Size

3.04 KB

Version

2

Bits

09d8d508

Nonce

217,565

Timestamp

9/2/2013, 6:59:41 AM

Confirmations

6,657,355

Merkle Root

c50c10a7b7b48f5fd5f2e9ed4a406bff8c7985dd9acf2f57255e8040eb3eaf5f
Transactions (5)
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.

1.756 × 10⁹³(94-digit number)
17568587989831060151…99609833531063010879
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
1.756 × 10⁹³(94-digit number)
17568587989831060151…99609833531063010879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.513 × 10⁹³(94-digit number)
35137175979662120302…99219667062126021759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.027 × 10⁹³(94-digit number)
70274351959324240605…98439334124252043519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.405 × 10⁹⁴(95-digit number)
14054870391864848121…96878668248504087039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.810 × 10⁹⁴(95-digit number)
28109740783729696242…93757336497008174079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.621 × 10⁹⁴(95-digit number)
56219481567459392484…87514672994016348159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.124 × 10⁹⁵(96-digit number)
11243896313491878496…75029345988032696319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.248 × 10⁹⁵(96-digit number)
22487792626983756993…50058691976065392639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.497 × 10⁹⁵(96-digit number)
44975585253967513987…00117383952130785279
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:57,671,569 XPM·at block #6,803,442 · updates every 60s
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