Block #854,293

1CCLength 11★★★☆☆

Cunningham Chain of the First Kind · Discovered 12/15/2014, 12:40:20 PM · Difficulty 10.9687 · 5,948,772 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
09a0b553c6fdd076e824d0668fe8147804ab35e4bdd78bfd0e8e7c55d46ba694

Height

#854,293

Difficulty

10.968654

Transactions

6

Size

1.59 KB

Version

2

Bits

0af7f9b5

Nonce

56,796,104

Timestamp

12/15/2014, 12:40:20 PM

Confirmations

5,948,772

Merkle Root

2109d21a19f79f97506c1500504444eb7918839efb570a22fe023f59efd5af7c
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.

3.085 × 10⁹⁵(96-digit number)
30858207793079201116…78962576969794257839
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
3.085 × 10⁹⁵(96-digit number)
30858207793079201116…78962576969794257839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
6.171 × 10⁹⁵(96-digit number)
61716415586158402232…57925153939588515679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.234 × 10⁹⁶(97-digit number)
12343283117231680446…15850307879177031359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
2.468 × 10⁹⁶(97-digit number)
24686566234463360893…31700615758354062719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
4.937 × 10⁹⁶(97-digit number)
49373132468926721786…63401231516708125439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
9.874 × 10⁹⁶(97-digit number)
98746264937853443572…26802463033416250879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.974 × 10⁹⁷(98-digit number)
19749252987570688714…53604926066832501759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.949 × 10⁹⁷(98-digit number)
39498505975141377428…07209852133665003519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
7.899 × 10⁹⁷(98-digit number)
78997011950282754857…14419704267330007039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
1.579 × 10⁹⁸(99-digit number)
15799402390056550971…28839408534660014079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
11
2^10 × origin − 1
3.159 × 10⁹⁸(99-digit number)
31598804780113101943…57678817069320028159
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:57,668,548 XPM·at block #6,803,064 · updates every 60s
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