Block #378,293

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/27/2014, 5:19:56 PM · Difficulty 10.4219 · 6,416,651 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
95e22cb2e88d84b5012d59f866d6c773656d97ebe38e75916abc04431eb14718

Height

#378,293

Difficulty

10.421856

Transactions

4

Size

884 B

Version

2

Bits

0a6bfec2

Nonce

44,464

Timestamp

1/27/2014, 5:19:56 PM

Confirmations

6,416,651

Merkle Root

98ec1ed12fe38083434480ed7f0336af5f9d1e9b3c08ba14f4dd9b5ea2eb0ea9
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.

3.100 × 10⁹¹(92-digit number)
31004044159582330282…13764999972961349969
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
3.100 × 10⁹¹(92-digit number)
31004044159582330282…13764999972961349969
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.100 × 10⁹¹(92-digit number)
31004044159582330282…13764999972961349971
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
6.200 × 10⁹¹(92-digit number)
62008088319164660564…27529999945922699939
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
6.200 × 10⁹¹(92-digit number)
62008088319164660564…27529999945922699941
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
1.240 × 10⁹²(93-digit number)
12401617663832932112…55059999891845399879
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.240 × 10⁹²(93-digit number)
12401617663832932112…55059999891845399881
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
2.480 × 10⁹²(93-digit number)
24803235327665864225…10119999783690799759
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.480 × 10⁹²(93-digit number)
24803235327665864225…10119999783690799761
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
4.960 × 10⁹²(93-digit number)
49606470655331728451…20239999567381599519
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.960 × 10⁹²(93-digit number)
49606470655331728451…20239999567381599521
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:57,603,587 XPM·at block #6,794,943 · updates every 60s
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