Block #449,203

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 3/18/2014, 10:56:12 AM · Difficulty 10.3693 · 6,344,363 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
9ed116c407a28bdcb5e2af1b64f4bc31af7ed82f9859c6226f7ed132ce59d80e

Height

#449,203

Difficulty

10.369293

Transactions

2

Size

1.70 KB

Version

2

Bits

0a5e89f7

Nonce

214,283

Timestamp

3/18/2014, 10:56:12 AM

Confirmations

6,344,363

Merkle Root

0919cd6058edb2a3f30cb1c5d86c30264b70e6ddf0cbb4a0ec6d91f7dcd35895
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.

4.920 × 10⁹³(94-digit number)
49202550229628991625…29221688460750495999
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
4.920 × 10⁹³(94-digit number)
49202550229628991625…29221688460750495999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
9.840 × 10⁹³(94-digit number)
98405100459257983250…58443376921500991999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.968 × 10⁹⁴(95-digit number)
19681020091851596650…16886753843001983999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.936 × 10⁹⁴(95-digit number)
39362040183703193300…33773507686003967999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.872 × 10⁹⁴(95-digit number)
78724080367406386600…67547015372007935999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.574 × 10⁹⁵(96-digit number)
15744816073481277320…35094030744015871999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
3.148 × 10⁹⁵(96-digit number)
31489632146962554640…70188061488031743999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
6.297 × 10⁹⁵(96-digit number)
62979264293925109280…40376122976063487999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.259 × 10⁹⁶(97-digit number)
12595852858785021856…80752245952126975999
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.519 × 10⁹⁶(97-digit number)
25191705717570043712…61504491904253951999
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:57,592,523 XPM·at block #6,793,565 · updates every 60s
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