Block #511,735

1CCLength 12★★★★☆

Cunningham Chain of the First Kind · Discovered 4/26/2014, 10:40:43 AM · Difficulty 10.8308 · 6,292,042 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
c8c5d0fe2ebea5e7a88736d223b8a65a520faae46385c13b2cca922725b3141f

Height

#511,735

Difficulty

10.830827

Transactions

5

Size

1.95 KB

Version

2

Bits

0ad4b112

Nonce

9,064

Timestamp

4/26/2014, 10:40:43 AM

Confirmations

6,292,042

Merkle Root

5a4640a3aca9791b0cfebcf3799d733b02cae023c5847a7ec7e575af13cc2c20
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.

9.542 × 10¹⁰¹(102-digit number)
95420434103604094204…71429285646313021439
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
9.542 × 10¹⁰¹(102-digit number)
95420434103604094204…71429285646313021439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
1.908 × 10¹⁰²(103-digit number)
19084086820720818840…42858571292626042879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
3.816 × 10¹⁰²(103-digit number)
38168173641441637681…85717142585252085759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
7.633 × 10¹⁰²(103-digit number)
76336347282883275363…71434285170504171519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.526 × 10¹⁰³(104-digit number)
15267269456576655072…42868570341008343039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.053 × 10¹⁰³(104-digit number)
30534538913153310145…85737140682016686079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
6.106 × 10¹⁰³(104-digit number)
61069077826306620290…71474281364033372159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.221 × 10¹⁰⁴(105-digit number)
12213815565261324058…42948562728066744319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.442 × 10¹⁰⁴(105-digit number)
24427631130522648116…85897125456133488639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
4.885 × 10¹⁰⁴(105-digit number)
48855262261045296232…71794250912266977279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
9.771 × 10¹⁰⁴(105-digit number)
97710524522090592465…43588501824533954559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
12
2^11 × origin − 1
1.954 × 10¹⁰⁵(106-digit number)
19542104904418118493…87177003649067909119
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 12 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
ExceptionalChain length 12

Around 1 in 10,000 blocks. A significant mathematical achievement.

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:57,674,255 XPM·at block #6,803,776 · updates every 60s
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