Block #471,748

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 4/2/2014, 7:16:07 PM · Difficulty 10.4358 · 6,331,050 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
fa282d0b6b6d08823f4caab77cf34d4ac55feddf99745691e03d4516b4f9d2c1

Height

#471,748

Difficulty

10.435801

Transactions

3

Size

2.31 KB

Version

2

Bits

0a6f90ae

Nonce

341,631

Timestamp

4/2/2014, 7:16:07 PM

Confirmations

6,331,050

Merkle Root

4797df54f266653c03ebbe174c48699160f98614543a0a2b8d5fec252618e704
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.

1.572 × 10¹⁰⁰(101-digit number)
15725215616942147072…83203014209049486719
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
1.572 × 10¹⁰⁰(101-digit number)
15725215616942147072…83203014209049486719
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
3.145 × 10¹⁰⁰(101-digit number)
31450431233884294144…66406028418098973439
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
6.290 × 10¹⁰⁰(101-digit number)
62900862467768588288…32812056836197946879
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
1.258 × 10¹⁰¹(102-digit number)
12580172493553717657…65624113672395893759
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
2.516 × 10¹⁰¹(102-digit number)
25160344987107435315…31248227344791787519
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
5.032 × 10¹⁰¹(102-digit number)
50320689974214870631…62496454689583575039
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
1.006 × 10¹⁰²(103-digit number)
10064137994842974126…24992909379167150079
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
2.012 × 10¹⁰²(103-digit number)
20128275989685948252…49985818758334300159
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
4.025 × 10¹⁰²(103-digit number)
40256551979371896504…99971637516668600319
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
8.051 × 10¹⁰²(103-digit number)
80513103958743793009…99943275033337200639
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:57,666,411 XPM·at block #6,802,797 · updates every 60s
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