Block #335,939

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 12/30/2013, 2:47:44 PM · Difficulty 10.1434 · 6,460,071 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
212e5fddf4e0f9b9143008bfaf206669b85c258011fb74a7b29240e90ea9cae4

Height

#335,939

Difficulty

10.143395

Transactions

12

Size

9.20 KB

Version

2

Bits

0a24b586

Nonce

57,771

Timestamp

12/30/2013, 2:47:44 PM

Confirmations

6,460,071

Merkle Root

ececf69d918f70bd08f822797c2369d8d80f1e84ad05192bef1a2eddfb9faf24
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.

1.293 × 10⁹⁹(100-digit number)
12937826831133110217…45627934248813332479
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
1.293 × 10⁹⁹(100-digit number)
12937826831133110217…45627934248813332479
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
1.293 × 10⁹⁹(100-digit number)
12937826831133110217…45627934248813332481
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
2.587 × 10⁹⁹(100-digit number)
25875653662266220435…91255868497626664959
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
2.587 × 10⁹⁹(100-digit number)
25875653662266220435…91255868497626664961
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
5.175 × 10⁹⁹(100-digit number)
51751307324532440870…82511736995253329919
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
5.175 × 10⁹⁹(100-digit number)
51751307324532440870…82511736995253329921
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
1.035 × 10¹⁰⁰(101-digit number)
10350261464906488174…65023473990506659839
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.035 × 10¹⁰⁰(101-digit number)
10350261464906488174…65023473990506659841
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
2.070 × 10¹⁰⁰(101-digit number)
20700522929812976348…30046947981013319679
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
2.070 × 10¹⁰⁰(101-digit number)
20700522929812976348…30046947981013319681
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:57,612,170 XPM·at block #6,796,009 · updates every 60s
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