Block #346,104

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/6/2014, 8:53:40 AM · Difficulty 10.2179 · 6,457,515 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
50188ab26886f76abe98749a8f26e23bffac11e75385cec8be1b9f37f70ef98e

Height

#346,104

Difficulty

10.217931

Transactions

16

Size

5.90 KB

Version

2

Bits

0a37ca56

Nonce

124,505

Timestamp

1/6/2014, 8:53:40 AM

Confirmations

6,457,515

Merkle Root

85831793e5a14a1697c4780e4e7a67c856ce5948bc2329aa231b7b0351983c77
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.

5.310 × 10¹⁰⁹(110-digit number)
53101340843785179568…65990105609233123839
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
5.310 × 10¹⁰⁹(110-digit number)
53101340843785179568…65990105609233123839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.062 × 10¹¹⁰(111-digit number)
10620268168757035913…31980211218466247679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.124 × 10¹¹⁰(111-digit number)
21240536337514071827…63960422436932495359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
4.248 × 10¹¹⁰(111-digit number)
42481072675028143654…27920844873864990719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
8.496 × 10¹¹⁰(111-digit number)
84962145350056287308…55841689747729981439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.699 × 10¹¹¹(112-digit number)
16992429070011257461…11683379495459962879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.398 × 10¹¹¹(112-digit number)
33984858140022514923…23366758990919925759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.796 × 10¹¹¹(112-digit number)
67969716280045029847…46733517981839851519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.359 × 10¹¹²(113-digit number)
13593943256009005969…93467035963679703039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.718 × 10¹¹²(113-digit number)
27187886512018011938…86934071927359406079
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:57,672,982 XPM·at block #6,803,618 · 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.