Block #468,495

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/31/2014, 1:23:22 PM · Difficulty 10.4313 · 6,335,271 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
84bffeae57473f08835cc535f8dace5400d20c3608c85709aee046064f7249db

Height

#468,495

Difficulty

10.431277

Transactions

6

Size

1.89 KB

Version

2

Bits

0a6e6824

Nonce

153,643

Timestamp

3/31/2014, 1:23:22 PM

Confirmations

6,335,271

Merkle Root

990df43add3fd1af1ca91492f10ac9aa72b6dbff376d580c3707377c7a864298
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.

3.607 × 10¹⁰²(103-digit number)
36079157736250741869…80952828754305074559
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
3.607 × 10¹⁰²(103-digit number)
36079157736250741869…80952828754305074559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
7.215 × 10¹⁰²(103-digit number)
72158315472501483738…61905657508610149119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.443 × 10¹⁰³(104-digit number)
14431663094500296747…23811315017220298239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.886 × 10¹⁰³(104-digit number)
28863326189000593495…47622630034440596479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
5.772 × 10¹⁰³(104-digit number)
57726652378001186991…95245260068881192959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.154 × 10¹⁰⁴(105-digit number)
11545330475600237398…90490520137762385919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.309 × 10¹⁰⁴(105-digit number)
23090660951200474796…80981040275524771839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
4.618 × 10¹⁰⁴(105-digit number)
46181321902400949592…61962080551049543679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
9.236 × 10¹⁰⁴(105-digit number)
92362643804801899185…23924161102099087359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.847 × 10¹⁰⁵(106-digit number)
18472528760960379837…47848322204198174719
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:57,674,165 XPM·at block #6,803,765 · updates every 60s
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