Block #449,242

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/18/2014, 11:25:45 AM · Difficulty 10.3702 · 6,348,910 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
16a0d2697622eaa8e467db259142bc916db3f984d8e5f582458cd92ac6652a39

Height

#449,242

Difficulty

10.370211

Transactions

2

Size

896 B

Version

2

Bits

0a5ec62d

Nonce

230,494

Timestamp

3/18/2014, 11:25:45 AM

Confirmations

6,348,910

Merkle Root

129d1c68a6b0db87f86acb33ba9a36cac16e7aaa5ff1b00334793cb110a839cf
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.

6.074 × 10⁹⁹(100-digit number)
60748313503490209605…93008092122894687189
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 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.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
6.074 × 10⁹⁹(100-digit number)
60748313503490209605…93008092122894687189
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
6.074 × 10⁹⁹(100-digit number)
60748313503490209605…93008092122894687191
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
1.214 × 10¹⁰⁰(101-digit number)
12149662700698041921…86016184245789374379
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.214 × 10¹⁰⁰(101-digit number)
12149662700698041921…86016184245789374381
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
2.429 × 10¹⁰⁰(101-digit number)
24299325401396083842…72032368491578748759
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.429 × 10¹⁰⁰(101-digit number)
24299325401396083842…72032368491578748761
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
4.859 × 10¹⁰⁰(101-digit number)
48598650802792167684…44064736983157497519
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.859 × 10¹⁰⁰(101-digit number)
48598650802792167684…44064736983157497521
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
9.719 × 10¹⁰⁰(101-digit number)
97197301605584335368…88129473966314995039
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
9.719 × 10¹⁰⁰(101-digit number)
97197301605584335368…88129473966314995041
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^4 × origin + 1 − 2^4 × origin − 1 = 2 (twin primes ✓)

What this block proved

The miner who found this block proved the existence of 10 consecutive prime numbers forming a Bi-Twin Chain. 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 TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Circulating Supply:57,629,215 XPM·at block #6,798,151 · updates every 60s
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