Block #784,276

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/26/2014, 6:44:49 PM · Difficulty 10.9751 · 6,011,316 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
2db8bdbe73ab58380dbaf4cd0fd95ba80a51ad26eb666fbb20dc4ea1dd50ea31

Height

#784,276

Difficulty

10.975124

Transactions

5

Size

13.30 KB

Version

2

Bits

0af9a1b2

Nonce

791,738,362

Timestamp

10/26/2014, 6:44:49 PM

Confirmations

6,011,316

Merkle Root

abd7dac94469ca9f44e9100a37a9d8372956b04920f457887d35ea0a7bea8eb7
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.

2.590 × 10⁹⁶(97-digit number)
25908240148579621953…41617354238753390079
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
2.590 × 10⁹⁶(97-digit number)
25908240148579621953…41617354238753390079
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.590 × 10⁹⁶(97-digit number)
25908240148579621953…41617354238753390081
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
5.181 × 10⁹⁶(97-digit number)
51816480297159243907…83234708477506780159
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.181 × 10⁹⁶(97-digit number)
51816480297159243907…83234708477506780161
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
1.036 × 10⁹⁷(98-digit number)
10363296059431848781…66469416955013560319
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.036 × 10⁹⁷(98-digit number)
10363296059431848781…66469416955013560321
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
2.072 × 10⁹⁷(98-digit number)
20726592118863697562…32938833910027120639
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.072 × 10⁹⁷(98-digit number)
20726592118863697562…32938833910027120641
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
4.145 × 10⁹⁷(98-digit number)
41453184237727395125…65877667820054241279
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
4.145 × 10⁹⁷(98-digit number)
41453184237727395125…65877667820054241281
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:57,608,799 XPM·at block #6,795,591 · updates every 60s
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