Block #365,791

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/18/2014, 11:56:54 PM · Difficulty 10.4256 · 6,429,013 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
53de076da542a7ce9caa141b5cce4d1c51327b54f4ccf787965d4c9915dc4bed

Height

#365,791

Difficulty

10.425647

Transactions

2

Size

718 B

Version

2

Bits

0a6cf732

Nonce

54,989

Timestamp

1/18/2014, 11:56:54 PM

Confirmations

6,429,013

Merkle Root

01983ebb2342fe1530e8738d8431e5f7b1ddd38363715aa8be464dc7e3c2c591
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.

3.388 × 10¹⁰²(103-digit number)
33889329781685607327…18797802307444591479
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
3.388 × 10¹⁰²(103-digit number)
33889329781685607327…18797802307444591479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.777 × 10¹⁰²(103-digit number)
67778659563371214654…37595604614889182959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.355 × 10¹⁰³(104-digit number)
13555731912674242930…75191209229778365919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.711 × 10¹⁰³(104-digit number)
27111463825348485861…50382418459556731839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.422 × 10¹⁰³(104-digit number)
54222927650696971723…00764836919113463679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.084 × 10¹⁰⁴(105-digit number)
10844585530139394344…01529673838226927359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.168 × 10¹⁰⁴(105-digit number)
21689171060278788689…03059347676453854719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.337 × 10¹⁰⁴(105-digit number)
43378342120557577379…06118695352907709439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
8.675 × 10¹⁰⁴(105-digit number)
86756684241115154758…12237390705815418879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.735 × 10¹⁰⁵(106-digit number)
17351336848223030951…24474781411630837759
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:57,602,477 XPM·at block #6,794,803 · updates every 60s
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