Block #480,459

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 4/8/2014, 8:00:11 AM · Difficulty 10.5163 · 6,321,003 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
fdf53bdb0705ec70e7578282978a3eebd72ac05aa42268cdc293893d8bca50fc

Height

#480,459

Difficulty

10.516299

Transactions

4

Size

1.69 KB

Version

2

Bits

0a842c32

Nonce

20,131

Timestamp

4/8/2014, 8:00:11 AM

Confirmations

6,321,003

Merkle Root

deebaae203a0ab37387a4e2f5d7776b5cce93bbdd948285c79c91f563140caf1
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.

3.081 × 10⁹³(94-digit number)
30815878869907458484…11291173771280855999
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
3.081 × 10⁹³(94-digit number)
30815878869907458484…11291173771280855999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.163 × 10⁹³(94-digit number)
61631757739814916968…22582347542561711999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.232 × 10⁹⁴(95-digit number)
12326351547962983393…45164695085123423999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.465 × 10⁹⁴(95-digit number)
24652703095925966787…90329390170246847999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.930 × 10⁹⁴(95-digit number)
49305406191851933574…80658780340493695999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.861 × 10⁹⁴(95-digit number)
98610812383703867149…61317560680987391999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.972 × 10⁹⁵(96-digit number)
19722162476740773429…22635121361974783999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.944 × 10⁹⁵(96-digit number)
39444324953481546859…45270242723949567999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.888 × 10⁹⁵(96-digit number)
78888649906963093719…90540485447899135999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.577 × 10⁹⁶(97-digit number)
15777729981392618743…81080970895798271999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.155 × 10⁹⁶(97-digit number)
31555459962785237487…62161941791596543999
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 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
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,655,770 XPM·at block #6,801,461 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.