Block #1,077,849

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 5/27/2015, 4:40:21 AM · Difficulty 10.7594 · 5,727,207 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
e148993c7fc9297900957b3bce059c25e6a65e98dd78ebd102b45969d1ca6211

Height

#1,077,849

Difficulty

10.759435

Transactions

2

Size

77.89 KB

Version

2

Bits

0ac26a54

Nonce

826,291,628

Timestamp

5/27/2015, 4:40:21 AM

Confirmations

5,727,207

Merkle Root

9e7cc845988de445f044f005dc77de779bb5d15eae6ebff26ac8d9584290c8ef
Transactions (2)
1 in → 1 out9.4200 XPM110 B
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.

1.218 × 10⁹⁵(96-digit number)
12186910087171775314…73549814399050349119
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
1.218 × 10⁹⁵(96-digit number)
12186910087171775314…73549814399050349119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.437 × 10⁹⁵(96-digit number)
24373820174343550629…47099628798100698239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.874 × 10⁹⁵(96-digit number)
48747640348687101258…94199257596201396479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.749 × 10⁹⁵(96-digit number)
97495280697374202517…88398515192402792959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.949 × 10⁹⁶(97-digit number)
19499056139474840503…76797030384805585919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.899 × 10⁹⁶(97-digit number)
38998112278949681006…53594060769611171839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.799 × 10⁹⁶(97-digit number)
77996224557899362013…07188121539222343679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.559 × 10⁹⁷(98-digit number)
15599244911579872402…14376243078444687359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.119 × 10⁹⁷(98-digit number)
31198489823159744805…28752486156889374719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
6.239 × 10⁹⁷(98-digit number)
62396979646319489611…57504972313778749439
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 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
UncommonChain length 10

Roughly 1 in 100 blocks. Solid but expected in a healthy network.

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:57,684,513 XPM·at block #6,805,055 · updates every 60s
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