Block #362,735

2CCLength 10★★☆☆☆

Cunningham Chain of the Second Kind · Discovered 1/16/2014, 9:51:28 PM · Difficulty 10.4179 · 6,433,332 confirmations

2CC
Cunningham Chain of the Second Kind

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

Block Header
Block Hash
8463fcd1476c1725687bcca543918b89eb8dcbe8940e0ce2f18c8b50aa17e964

Height

#362,735

Difficulty

10.417937

Transactions

2

Size

1.14 KB

Version

2

Bits

0a6afde8

Nonce

6,712

Timestamp

1/16/2014, 9:51:28 PM

Confirmations

6,433,332

Merkle Root

90d17ef7c8358780cf5fe0b3f7445aa481db80c4448f3f4b8a012b1868467d6b
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.

4.346 × 10¹⁰⁰(101-digit number)
43465613054200510683…93700594545691443201
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
4.346 × 10¹⁰⁰(101-digit number)
43465613054200510683…93700594545691443201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
2
2^1 × origin + 1
8.693 × 10¹⁰⁰(101-digit number)
86931226108401021366…87401189091382886401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
3
2^2 × origin + 1
1.738 × 10¹⁰¹(102-digit number)
17386245221680204273…74802378182765772801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
4
2^3 × origin + 1
3.477 × 10¹⁰¹(102-digit number)
34772490443360408546…49604756365531545601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
5
2^4 × origin + 1
6.954 × 10¹⁰¹(102-digit number)
69544980886720817092…99209512731063091201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
6
2^5 × origin + 1
1.390 × 10¹⁰²(103-digit number)
13908996177344163418…98419025462126182401
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
7
2^6 × origin + 1
2.781 × 10¹⁰²(103-digit number)
27817992354688326837…96838050924252364801
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
8
2^7 × origin + 1
5.563 × 10¹⁰²(103-digit number)
55635984709376653674…93676101848504729601
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
9
2^8 × origin + 1
1.112 × 10¹⁰³(104-digit number)
11127196941875330734…87352203697009459201
Verify on FactorDB ↗Wolfram Alpha ↗
×2−1 →
10
2^9 × origin + 1
2.225 × 10¹⁰³(104-digit number)
22254393883750661469…74704407394018918401
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 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
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 2CC formula:

2CC: p₁ (first prime), p₂ = 2p₁ − 1, p₃ = 2p₂ − 1, …
Circulating Supply:57,612,631 XPM·at block #6,796,066 · updates every 60s
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