Block #316,544

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/17/2013, 3:32:07 AM · Difficulty 10.1367 · 6,482,724 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
01cc93b07e94f7c9e70dd373738525e2d0844fcee25d11cce0f3ab254d7fd008

Height

#316,544

Difficulty

10.136703

Transactions

16

Size

11.61 KB

Version

2

Bits

0a22fef2

Nonce

142,915

Timestamp

12/17/2013, 3:32:07 AM

Confirmations

6,482,724

Merkle Root

c17f0eb46aa59c8bcd5aa2627e80288e5fe8957d4fdb4227647c8197f0cb8549
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.

1.488 × 10¹⁰²(103-digit number)
14889744248850982555…52164341278327530639
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
1.488 × 10¹⁰²(103-digit number)
14889744248850982555…52164341278327530639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.977 × 10¹⁰²(103-digit number)
29779488497701965111…04328682556655061279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.955 × 10¹⁰²(103-digit number)
59558976995403930223…08657365113310122559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.191 × 10¹⁰³(104-digit number)
11911795399080786044…17314730226620245119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.382 × 10¹⁰³(104-digit number)
23823590798161572089…34629460453240490239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.764 × 10¹⁰³(104-digit number)
47647181596323144178…69258920906480980479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
9.529 × 10¹⁰³(104-digit number)
95294363192646288356…38517841812961960959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.905 × 10¹⁰⁴(105-digit number)
19058872638529257671…77035683625923921919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.811 × 10¹⁰⁴(105-digit number)
38117745277058515342…54071367251847843839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.623 × 10¹⁰⁴(105-digit number)
76235490554117030685…08142734503695687679
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:57,638,183 XPM·at block #6,799,267 · updates every 60s
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