Block #335,627

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 12/30/2013, 9:30:24 AM · Difficulty 10.1442 · 6,467,829 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c640c3e23ce48f70e74970d22f355a3d5954c9f8c8e404d9f896e20612e5c3d6

Height

#335,627

Difficulty

10.144235

Transactions

7

Size

3.55 KB

Version

2

Bits

0a24ec96

Nonce

103,623

Timestamp

12/30/2013, 9:30:24 AM

Confirmations

6,467,829

Merkle Root

f5903a18fbe60dffce2710af47b95c162b46355ea50a3ad86e44cf6583393f8d
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.

9.733 × 10¹⁰⁴(105-digit number)
97336096661261715561…11426461984709994239
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
9.733 × 10¹⁰⁴(105-digit number)
97336096661261715561…11426461984709994239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.946 × 10¹⁰⁵(106-digit number)
19467219332252343112…22852923969419988479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.893 × 10¹⁰⁵(106-digit number)
38934438664504686224…45705847938839976959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.786 × 10¹⁰⁵(106-digit number)
77868877329009372449…91411695877679953919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.557 × 10¹⁰⁶(107-digit number)
15573775465801874489…82823391755359907839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.114 × 10¹⁰⁶(107-digit number)
31147550931603748979…65646783510719815679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.229 × 10¹⁰⁶(107-digit number)
62295101863207497959…31293567021439631359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.245 × 10¹⁰⁷(108-digit number)
12459020372641499591…62587134042879262719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.491 × 10¹⁰⁷(108-digit number)
24918040745282999183…25174268085758525439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.983 × 10¹⁰⁷(108-digit number)
49836081490565998367…50348536171517050879
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:57,671,675 XPM·at block #6,803,455 · updates every 60s
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