Block #232,099

1CCLength 9★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 10/28/2013, 9:26:46 PM · Difficulty 9.9410 · 6,560,681 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
df95986e0fa01f1f28b64d32ba79614258fd3c80ac5387ffc095ce29e44945ae

Height

#232,099

Difficulty

9.940951

Transactions

8

Size

24.96 KB

Version

2

Bits

09f0e22f

Nonce

42,027

Timestamp

10/28/2013, 9:26:46 PM

Confirmations

6,560,681

Merkle Root

4138e786a14792231d4240eed9bfa0207e49c937cb863754ad356ba4eb806aaf
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.

2.463 × 10⁹⁵(96-digit number)
24631078313252007722…41692714187271478239
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
2.463 × 10⁹⁵(96-digit number)
24631078313252007722…41692714187271478239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
4.926 × 10⁹⁵(96-digit number)
49262156626504015444…83385428374542956479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
9.852 × 10⁹⁵(96-digit number)
98524313253008030888…66770856749085912959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.970 × 10⁹⁶(97-digit number)
19704862650601606177…33541713498171825919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
3.940 × 10⁹⁶(97-digit number)
39409725301203212355…67083426996343651839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
7.881 × 10⁹⁶(97-digit number)
78819450602406424710…34166853992687303679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.576 × 10⁹⁷(98-digit number)
15763890120481284942…68333707985374607359
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
3.152 × 10⁹⁷(98-digit number)
31527780240962569884…36667415970749214719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
6.305 × 10⁹⁷(98-digit number)
63055560481925139768…73334831941498429439
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:57,586,222 XPM·at block #6,792,779 · updates every 60s
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