Block #441,618

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/13/2014, 6:43:53 AM · Difficulty 10.3481 · 6,352,929 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
26ba500f31db8a65f936daa4235b1ceff725969ec1d03968fb11860d6a37f909

Height

#441,618

Difficulty

10.348078

Transactions

4

Size

1.51 KB

Version

2

Bits

0a591ba8

Nonce

3,940

Timestamp

3/13/2014, 6:43:53 AM

Confirmations

6,352,929

Merkle Root

b21350739ac88721c63f3499a451ff48d2e2c5c67210aa45c209c7f4b33a6343
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.

2.383 × 10⁹⁹(100-digit number)
23832826831094293322…38033262519215374719
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
2.383 × 10⁹⁹(100-digit number)
23832826831094293322…38033262519215374719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.766 × 10⁹⁹(100-digit number)
47665653662188586644…76066525038430749439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.533 × 10⁹⁹(100-digit number)
95331307324377173289…52133050076861498879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.906 × 10¹⁰⁰(101-digit number)
19066261464875434657…04266100153722997759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.813 × 10¹⁰⁰(101-digit number)
38132522929750869315…08532200307445995519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.626 × 10¹⁰⁰(101-digit number)
76265045859501738631…17064400614891991039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.525 × 10¹⁰¹(102-digit number)
15253009171900347726…34128801229783982079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.050 × 10¹⁰¹(102-digit number)
30506018343800695452…68257602459567964159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.101 × 10¹⁰¹(102-digit number)
61012036687601390905…36515204919135928319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.220 × 10¹⁰²(103-digit number)
12202407337520278181…73030409838271856639
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:57,600,416 XPM·at block #6,794,546 · 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.