Block #1,086,077

2CCLength 11★★★☆☆

Cunningham Chain of the Second Kind · Discovered 6/2/2015, 12:29:36 AM · Difficulty 10.7519 · 5,717,991 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
2ae64830e1b42ea809e6afef03de062065fb07816fff9576c174969279132f59

Height

#1,086,077

Difficulty

10.751919

Transactions

5

Size

1.08 KB

Version

2

Bits

0ac07dbd

Nonce

81,052,992

Timestamp

6/2/2015, 12:29:36 AM

Confirmations

5,717,991

Merkle Root

92a38e7aae2cccdbba850250542cee44f3bb2b6ba658abda1397d0f549a48bf1
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.

1.383 × 10⁹⁷(98-digit number)
13830590679994769630…40747074578460672001
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
1.383 × 10⁹⁷(98-digit number)
13830590679994769630…40747074578460672001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
2.766 × 10⁹⁷(98-digit number)
27661181359989539260…81494149156921344001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
5.532 × 10⁹⁷(98-digit number)
55322362719979078521…62988298313842688001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
1.106 × 10⁹⁸(99-digit number)
11064472543995815704…25976596627685376001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
2.212 × 10⁹⁸(99-digit number)
22128945087991631408…51953193255370752001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
4.425 × 10⁹⁸(99-digit number)
44257890175983262816…03906386510741504001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
8.851 × 10⁹⁸(99-digit number)
88515780351966525633…07812773021483008001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
1.770 × 10⁹⁹(100-digit number)
17703156070393305126…15625546042966016001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
3.540 × 10⁹⁹(100-digit number)
35406312140786610253…31251092085932032001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
7.081 × 10⁹⁹(100-digit number)
70812624281573220507…62502184171864064001
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
11
2^10 × origin + 1
1.416 × 10¹⁰⁰(101-digit number)
14162524856314644101…25004368343728128001
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 consecutive prime numbers forming a Cunningham Chain of the Second 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,676,599 XPM·at block #6,804,067 · updates every 60s
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