Block #448,482

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 3/17/2014, 11:06:27 PM · Difficulty 10.3677 · 6,348,166 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
927b4511498f36393ba085ec2d40225343439bff94f2ea409bbbfa65e67d2746

Height

#448,482

Difficulty

10.367729

Transactions

3

Size

1.48 KB

Version

2

Bits

0a5e2385

Nonce

138,705

Timestamp

3/17/2014, 11:06:27 PM

Confirmations

6,348,166

Merkle Root

d0210f0d53bb75a44dfd8eaea77c6188365dea2a5639227e5fbdd4b80fb614d1
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.

7.266 × 10¹⁰⁰(101-digit number)
72661706123400775104…20247821889184665599
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
7.266 × 10¹⁰⁰(101-digit number)
72661706123400775104…20247821889184665599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.453 × 10¹⁰¹(102-digit number)
14532341224680155020…40495643778369331199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
2.906 × 10¹⁰¹(102-digit number)
29064682449360310041…80991287556738662399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
5.812 × 10¹⁰¹(102-digit number)
58129364898720620083…61982575113477324799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.162 × 10¹⁰²(103-digit number)
11625872979744124016…23965150226954649599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
2.325 × 10¹⁰²(103-digit number)
23251745959488248033…47930300453909299199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
4.650 × 10¹⁰²(103-digit number)
46503491918976496066…95860600907818598399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
9.300 × 10¹⁰²(103-digit number)
93006983837952992133…91721201815637196799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.860 × 10¹⁰³(104-digit number)
18601396767590598426…83442403631274393599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
3.720 × 10¹⁰³(104-digit number)
37202793535181196853…66884807262548787199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
7.440 × 10¹⁰³(104-digit number)
74405587070362393706…33769614525097574399
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 11 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
RareChain length 11

Approximately 1 in 1,000 blocks. Noteworthy discoveries.

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:57,617,187 XPM·at block #6,796,647 · updates every 60s
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