Block #273,994

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 11/26/2013, 2:21:56 AM · Difficulty 9.9561 · 6,518,216 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f73314c84dfa839b211d47b8c6aa9fb3ffb6ae66b769bda72ed5d9f3423f9d0d

Height

#273,994

Difficulty

9.956129

Transactions

6

Size

38.26 KB

Version

2

Bits

09f4c4d9

Nonce

25,307

Timestamp

11/26/2013, 2:21:56 AM

Confirmations

6,518,216

Merkle Root

31aeab928c87dcd70f66456d8a9ff0c59a9a06b1417fe05b1fb40aa97f4f65ce
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.

2.415 × 10⁹⁷(98-digit number)
24151086307433224036…70472710193217116159
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
2.415 × 10⁹⁷(98-digit number)
24151086307433224036…70472710193217116159
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.415 × 10⁹⁷(98-digit number)
24151086307433224036…70472710193217116161
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
4.830 × 10⁹⁷(98-digit number)
48302172614866448072…40945420386434232319
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.830 × 10⁹⁷(98-digit number)
48302172614866448072…40945420386434232321
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
9.660 × 10⁹⁷(98-digit number)
96604345229732896144…81890840772868464639
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.660 × 10⁹⁷(98-digit number)
96604345229732896144…81890840772868464641
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
1.932 × 10⁹⁸(99-digit number)
19320869045946579228…63781681545736929279
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.932 × 10⁹⁸(99-digit number)
19320869045946579228…63781681545736929281
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
3.864 × 10⁹⁸(99-digit number)
38641738091893158457…27563363091473858559
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.864 × 10⁹⁸(99-digit number)
38641738091893158457…27563363091473858561
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:57,581,634 XPM·at block #6,792,209 · updates every 60s
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