Block #449,124

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 3/18/2014, 9:49:30 AM · Difficulty 10.3681 · 6,350,195 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
503b751dc07e8e5749ac21c377a7ede0e05d6c6396b7eae3f5363b6be565d5d1

Height

#449,124

Difficulty

10.368143

Transactions

16

Size

23.93 KB

Version

2

Bits

0a5e3ea1

Nonce

100,336,991

Timestamp

3/18/2014, 9:49:30 AM

Confirmations

6,350,195

Merkle Root

3c0ab800b0548a4ac6c9d78aa666570897855b7c09c71b9ba01f82d62daf4c33
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.

1.354 × 10⁹⁸(99-digit number)
13541780333764467999…96460934353445519359
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
1.354 × 10⁹⁸(99-digit number)
13541780333764467999…96460934353445519359
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.354 × 10⁹⁸(99-digit number)
13541780333764467999…96460934353445519361
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
2.708 × 10⁹⁸(99-digit number)
27083560667528935998…92921868706891038719
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.708 × 10⁹⁸(99-digit number)
27083560667528935998…92921868706891038721
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
5.416 × 10⁹⁸(99-digit number)
54167121335057871997…85843737413782077439
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.416 × 10⁹⁸(99-digit number)
54167121335057871997…85843737413782077441
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
1.083 × 10⁹⁹(100-digit number)
10833424267011574399…71687474827564154879
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.083 × 10⁹⁹(100-digit number)
10833424267011574399…71687474827564154881
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
2.166 × 10⁹⁹(100-digit number)
21666848534023148799…43374949655128309759
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.166 × 10⁹⁹(100-digit number)
21666848534023148799…43374949655128309761
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:57,638,600 XPM·at block #6,799,318 · updates every 60s
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