Block #472,085

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/3/2014, 1:15:16 AM · Difficulty 10.4337 · 6,323,726 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9693f94117dd92da284bb6f18698934129665e45a85069ea0f3ec7183ab83ed4

Height

#472,085

Difficulty

10.433654

Transactions

2

Size

857 B

Version

2

Bits

0a6f03f8

Nonce

7,357,114

Timestamp

4/3/2014, 1:15:16 AM

Confirmations

6,323,726

Merkle Root

af8a7671213a58e98eb38b5ddead59b28f2e2ff635ef240d586df07fa7b4fc5b
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.

2.855 × 10⁹⁴(95-digit number)
28551130887896436008…18377193523958364009
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
2.855 × 10⁹⁴(95-digit number)
28551130887896436008…18377193523958364009
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
5.710 × 10⁹⁴(95-digit number)
57102261775792872017…36754387047916728019
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.142 × 10⁹⁵(96-digit number)
11420452355158574403…73508774095833456039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.284 × 10⁹⁵(96-digit number)
22840904710317148806…47017548191666912079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.568 × 10⁹⁵(96-digit number)
45681809420634297613…94035096383333824159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.136 × 10⁹⁵(96-digit number)
91363618841268595227…88070192766667648319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.827 × 10⁹⁶(97-digit number)
18272723768253719045…76140385533335296639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.654 × 10⁹⁶(97-digit number)
36545447536507438090…52280771066670593279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.309 × 10⁹⁶(97-digit number)
73090895073014876181…04561542133341186559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.461 × 10⁹⁷(98-digit number)
14618179014602975236…09123084266682373119
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:57,610,568 XPM·at block #6,795,810 · updates every 60s
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