Block #493,337

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 4/15/2014, 3:50:14 PM · Difficulty 10.6980 · 6,309,727 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
e9b8622c67363e2f15a2bddee266605c58a0727f1bf324e8e00ea2e1fdca09e1

Height

#493,337

Difficulty

10.698029

Transactions

1

Size

971 B

Version

2

Bits

0ab2b204

Nonce

33,791

Timestamp

4/15/2014, 3:50:14 PM

Confirmations

6,309,727

Merkle Root

ecd839dbd37bea560d9d0226dfeeea92a380e25eab6da9c77821e31c90ca2d34
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.

3.650 × 10⁹⁹(100-digit number)
36505879654232125510…21494122223780382559
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
3.650 × 10⁹⁹(100-digit number)
36505879654232125510…21494122223780382559
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
3.650 × 10⁹⁹(100-digit number)
36505879654232125510…21494122223780382561
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
7.301 × 10⁹⁹(100-digit number)
73011759308464251020…42988244447560765119
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
7.301 × 10⁹⁹(100-digit number)
73011759308464251020…42988244447560765121
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
1.460 × 10¹⁰⁰(101-digit number)
14602351861692850204…85976488895121530239
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.460 × 10¹⁰⁰(101-digit number)
14602351861692850204…85976488895121530241
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
2.920 × 10¹⁰⁰(101-digit number)
29204703723385700408…71952977790243060479
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.920 × 10¹⁰⁰(101-digit number)
29204703723385700408…71952977790243060481
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
5.840 × 10¹⁰⁰(101-digit number)
58409407446771400816…43905955580486120959
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
5.840 × 10¹⁰⁰(101-digit number)
58409407446771400816…43905955580486120961
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:57,668,540 XPM·at block #6,803,063 · updates every 60s
xpmprime.info is a work in progress. If you enjoy using this service you can support this project with a Primecoin donation.