Block #354,986

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 1/11/2014, 9:00:58 PM · Difficulty 10.3543 · 6,447,604 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
c87f6cc3901b0a9fdb3d9947f55324d16ef0d869f76067d2dcfe6c497e6e5ff0

Height

#354,986

Difficulty

10.354317

Transactions

16

Size

4.61 KB

Version

2

Bits

0a5ab47f

Nonce

49,634

Timestamp

1/11/2014, 9:00:58 PM

Confirmations

6,447,604

Merkle Root

5292276850b1e5a027af26fc8f5535566cae78a504bbb606dd39fa7e2404b96c
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.

1.005 × 10¹⁰²(103-digit number)
10057622012358175105…16814104947924713399
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
1.005 × 10¹⁰²(103-digit number)
10057622012358175105…16814104947924713399
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.005 × 10¹⁰²(103-digit number)
10057622012358175105…16814104947924713401
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
2.011 × 10¹⁰²(103-digit number)
20115244024716350210…33628209895849426799
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.011 × 10¹⁰²(103-digit number)
20115244024716350210…33628209895849426801
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
4.023 × 10¹⁰²(103-digit number)
40230488049432700421…67256419791698853599
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
4.023 × 10¹⁰²(103-digit number)
40230488049432700421…67256419791698853601
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
8.046 × 10¹⁰²(103-digit number)
80460976098865400843…34512839583397707199
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
8.046 × 10¹⁰²(103-digit number)
80460976098865400843…34512839583397707201
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
1.609 × 10¹⁰³(104-digit number)
16092195219773080168…69025679166795414399
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.609 × 10¹⁰³(104-digit number)
16092195219773080168…69025679166795414401
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:57,664,738 XPM·at block #6,802,589 · updates every 60s
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