Block #336,701

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/31/2013, 3:42:56 AM · Difficulty 10.1413 · 6,462,778 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
54db9d340d52b4f5215e3a4c1b2f4cef9e5d9502f80d310f4e3ee5e76a95f5b9

Height

#336,701

Difficulty

10.141301

Transactions

4

Size

2.74 KB

Version

2

Bits

0a242c54

Nonce

339,095

Timestamp

12/31/2013, 3:42:56 AM

Confirmations

6,462,778

Merkle Root

5c60f52fe843c9357186b05293c3f323e63f9caf7990c6ac09c624bb4ae1a068
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.

1.379 × 10⁹⁶(97-digit number)
13795793658859278449…10642126502118225919
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
1.379 × 10⁹⁶(97-digit number)
13795793658859278449…10642126502118225919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.759 × 10⁹⁶(97-digit number)
27591587317718556898…21284253004236451839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
5.518 × 10⁹⁶(97-digit number)
55183174635437113797…42568506008472903679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.103 × 10⁹⁷(98-digit number)
11036634927087422759…85137012016945807359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.207 × 10⁹⁷(98-digit number)
22073269854174845519…70274024033891614719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
4.414 × 10⁹⁷(98-digit number)
44146539708349691038…40548048067783229439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
8.829 × 10⁹⁷(98-digit number)
88293079416699382076…81096096135566458879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.765 × 10⁹⁸(99-digit number)
17658615883339876415…62192192271132917759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
3.531 × 10⁹⁸(99-digit number)
35317231766679752830…24384384542265835519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
7.063 × 10⁹⁸(99-digit number)
70634463533359505661…48768769084531671039
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:57,639,874 XPM·at block #6,799,478 · updates every 60s
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