Block #389,321

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 2/4/2014, 10:05:13 AM · Difficulty 10.4194 · 6,408,881 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
6be2946c1ad9fbc1fa59ba520e6ee6b3e3c41207d6e6ebd910a7877ac9778359

Height

#389,321

Difficulty

10.419424

Transactions

5

Size

4.28 KB

Version

2

Bits

0a6b5f62

Nonce

38,128

Timestamp

2/4/2014, 10:05:13 AM

Confirmations

6,408,881

Merkle Root

d23349de37632df7d3ca48e0e7b20ff98939058fe8695e8caf868b5bfb7ff5ee
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.

5.143 × 10¹⁰¹(102-digit number)
51434873393890347323…28445089889908633599
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
5.143 × 10¹⁰¹(102-digit number)
51434873393890347323…28445089889908633599
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.143 × 10¹⁰¹(102-digit number)
51434873393890347323…28445089889908633601
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
1.028 × 10¹⁰²(103-digit number)
10286974678778069464…56890179779817267199
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.028 × 10¹⁰²(103-digit number)
10286974678778069464…56890179779817267201
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
2.057 × 10¹⁰²(103-digit number)
20573949357556138929…13780359559634534399
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.057 × 10¹⁰²(103-digit number)
20573949357556138929…13780359559634534401
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
4.114 × 10¹⁰²(103-digit number)
41147898715112277858…27560719119269068799
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.114 × 10¹⁰²(103-digit number)
41147898715112277858…27560719119269068801
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
8.229 × 10¹⁰²(103-digit number)
82295797430224555717…55121438238538137599
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.229 × 10¹⁰²(103-digit number)
82295797430224555717…55121438238538137601
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:57,629,622 XPM·at block #6,798,201 · updates every 60s
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