Block #457,165

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/23/2014, 5:07:41 PM · Difficulty 10.4213 · 6,338,826 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
019de1129daca22435c930423d9839e8ef0472df7d35532db39aad14e4fdcaa6

Height

#457,165

Difficulty

10.421313

Transactions

1

Size

868 B

Version

2

Bits

0a6bdb2a

Nonce

18,992

Timestamp

3/23/2014, 5:07:41 PM

Confirmations

6,338,826

Merkle Root

9df0980f966ff16705298a8a87db34ec0551de2f2837b9c61d1828c9c736ceb7
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.

1.904 × 10⁹⁷(98-digit number)
19046331459757769745…68486370443653488639
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
1.904 × 10⁹⁷(98-digit number)
19046331459757769745…68486370443653488639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.809 × 10⁹⁷(98-digit number)
38092662919515539490…36972740887306977279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
7.618 × 10⁹⁷(98-digit number)
76185325839031078981…73945481774613954559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.523 × 10⁹⁸(99-digit number)
15237065167806215796…47890963549227909119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.047 × 10⁹⁸(99-digit number)
30474130335612431592…95781927098455818239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
6.094 × 10⁹⁸(99-digit number)
60948260671224863184…91563854196911636479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.218 × 10⁹⁹(100-digit number)
12189652134244972636…83127708393823272959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.437 × 10⁹⁹(100-digit number)
24379304268489945273…66255416787646545919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.875 × 10⁹⁹(100-digit number)
48758608536979890547…32510833575293091839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
9.751 × 10⁹⁹(100-digit number)
97517217073959781095…65021667150586183679
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:57,612,024 XPM·at block #6,795,990 · 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.