Block #89,359

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/30/2013, 7:32:13 AM · Difficulty 9.2599 · 6,705,527 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
91797f56cda44e59062ba253b6137c65e9c3cb4eff9a18009f5bfb4286004b17

Height

#89,359

Difficulty

9.259899

Transactions

2

Size

429 B

Version

2

Bits

094288c6

Nonce

61,796

Timestamp

7/30/2013, 7:32:13 AM

Confirmations

6,705,527

Merkle Root

9dcc3ba47468b3fe4814b923b2c8781035df2259a7fe7aacb5c46f080ba4b8ad
Transactions (2)
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.

1.160 × 10¹⁰⁴(105-digit number)
11606682538586249306…68543406980500002819
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
1.160 × 10¹⁰⁴(105-digit number)
11606682538586249306…68543406980500002819
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
2.321 × 10¹⁰⁴(105-digit number)
23213365077172498612…37086813961000005639
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
4.642 × 10¹⁰⁴(105-digit number)
46426730154344997225…74173627922000011279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
9.285 × 10¹⁰⁴(105-digit number)
92853460308689994451…48347255844000022559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
1.857 × 10¹⁰⁵(106-digit number)
18570692061737998890…96694511688000045119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
3.714 × 10¹⁰⁵(106-digit number)
37141384123475997780…93389023376000090239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
7.428 × 10¹⁰⁵(106-digit number)
74282768246951995560…86778046752000180479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
1.485 × 10¹⁰⁶(107-digit number)
14856553649390399112…73556093504000360959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
2.971 × 10¹⁰⁶(107-digit number)
29713107298780798224…47112187008000721919
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 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
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

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:57,603,123 XPM·at block #6,794,885 · updates every 60s
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