Block #474,038

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/4/2014, 7:57:07 AM · Difficulty 10.4471 · 6,324,999 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
36331440c36f0c8ebbafc00a61fab23fe1c2498826f308ffb095eb34ee34cfa5

Height

#474,038

Difficulty

10.447150

Transactions

2

Size

1.31 KB

Version

2

Bits

0a727865

Nonce

43,190

Timestamp

4/4/2014, 7:57:07 AM

Confirmations

6,324,999

Merkle Root

c452ee7433378239dbaa02c98e155d6766d7e7f930524a8c83648420a2620fa2
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.

2.474 × 10⁹⁸(99-digit number)
24741307969373366189…40008843192924899039
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
2.474 × 10⁹⁸(99-digit number)
24741307969373366189…40008843192924899039
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.474 × 10⁹⁸(99-digit number)
24741307969373366189…40008843192924899041
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
4.948 × 10⁹⁸(99-digit number)
49482615938746732379…80017686385849798079
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
4.948 × 10⁹⁸(99-digit number)
49482615938746732379…80017686385849798081
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
9.896 × 10⁹⁸(99-digit number)
98965231877493464759…60035372771699596159
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
9.896 × 10⁹⁸(99-digit number)
98965231877493464759…60035372771699596161
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
1.979 × 10⁹⁹(100-digit number)
19793046375498692951…20070745543399192319
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
1.979 × 10⁹⁹(100-digit number)
19793046375498692951…20070745543399192321
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
3.958 × 10⁹⁹(100-digit number)
39586092750997385903…40141491086798384639
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
3.958 × 10⁹⁹(100-digit number)
39586092750997385903…40141491086798384641
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:57,636,335 XPM·at block #6,799,036 · updates every 60s
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