Block #212,934

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 10/16/2013, 2:39:53 PM · Difficulty 9.9197 · 6,589,872 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
973154646aaf83e230c7bbf4e09ebe230415715bf09923b9869e9ae8ed3f480e

Height

#212,934

Difficulty

9.919665

Transactions

8

Size

1.83 KB

Version

2

Bits

09eb6f31

Nonce

54,268

Timestamp

10/16/2013, 2:39:53 PM

Confirmations

6,589,872

Merkle Root

65eeb9fc5f330baec36f883ab740acf57ef0dd36f19b585ae3b494fad7251ad8
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.

5.034 × 10⁹⁸(99-digit number)
50341202318158748180…73231022238255201279
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
5.034 × 10⁹⁸(99-digit number)
50341202318158748180…73231022238255201279
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
5.034 × 10⁹⁸(99-digit number)
50341202318158748180…73231022238255201281
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
1.006 × 10⁹⁹(100-digit number)
10068240463631749636…46462044476510402559
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.006 × 10⁹⁹(100-digit number)
10068240463631749636…46462044476510402561
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
2.013 × 10⁹⁹(100-digit number)
20136480927263499272…92924088953020805119
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
2.013 × 10⁹⁹(100-digit number)
20136480927263499272…92924088953020805121
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
4.027 × 10⁹⁹(100-digit number)
40272961854526998544…85848177906041610239
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
4.027 × 10⁹⁹(100-digit number)
40272961854526998544…85848177906041610241
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
8.054 × 10⁹⁹(100-digit number)
80545923709053997089…71696355812083220479
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
8.054 × 10⁹⁹(100-digit number)
80545923709053997089…71696355812083220481
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:57,666,476 XPM·at block #6,802,805 · updates every 60s
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