Block #477,657

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 4/6/2014, 2:23:39 PM · Difficulty 10.4867 · 6,325,821 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
007425ec7c5d0fbf5a892938bb105077ba2cc2e6a4f5b22bdf492c1763c147ea

Height

#477,657

Difficulty

10.486687

Transactions

1

Size

936 B

Version

2

Bits

0a7c9783

Nonce

29,483

Timestamp

4/6/2014, 2:23:39 PM

Confirmations

6,325,821

Merkle Root

89a1543a20f0f07fa61d29be956f3472f23d6fb0bd05e81d6def6272b9802dcd
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.

1.960 × 10⁹⁶(97-digit number)
19604050121309515491…04875871389204590399
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
1.960 × 10⁹⁶(97-digit number)
19604050121309515491…04875871389204590399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.920 × 10⁹⁶(97-digit number)
39208100242619030982…09751742778409180799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.841 × 10⁹⁶(97-digit number)
78416200485238061965…19503485556818361599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.568 × 10⁹⁷(98-digit number)
15683240097047612393…39006971113636723199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.136 × 10⁹⁷(98-digit number)
31366480194095224786…78013942227273446399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.273 × 10⁹⁷(98-digit number)
62732960388190449572…56027884454546892799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.254 × 10⁹⁸(99-digit number)
12546592077638089914…12055768909093785599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.509 × 10⁹⁸(99-digit number)
25093184155276179829…24111537818187571199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
5.018 × 10⁹⁸(99-digit number)
50186368310552359658…48223075636375142399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.003 × 10⁹⁹(100-digit number)
10037273662110471931…96446151272750284799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
2.007 × 10⁹⁹(100-digit number)
20074547324220943863…92892302545500569599
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:57,671,853 XPM·at block #6,803,477 · 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.