Home/Chain Registry/Block #706,647

Block #706,647

TWNLength 10★★☆☆☆

Bi-Twin Chain · Discovered 9/4/2014, 8:04:50 AM · Difficulty 10.9587 · 6,085,640 confirmations

TWN
Bi-Twin Chain

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

Block Header
Block Hash
f4d51cfd86a6b7a6dde05ea90f86227e49227e0bfa71cd24e9478d6e90c5ff7a

Height

#706,647

Difficulty

10.958709

Transactions

5

Size

2.73 KB

Version

2

Bits

0af56df5

Nonce

969,135,362

Timestamp

9/4/2014, 8:04:50 AM

Confirmations

6,085,640

Merkle Root

7cf019a3cfb8b2047384b5e4e0baf5d327bcd2e111d012975c99b80bd561a21d
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.

9.085 × 10⁹⁶(97-digit number)
90851440566175104453…93822325774037809920
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
9.085 × 10⁹⁶(97-digit number)
90851440566175104453…93822325774037809919
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
9.085 × 10⁹⁶(97-digit number)
90851440566175104453…93822325774037809921
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
1.817 × 10⁹⁷(98-digit number)
18170288113235020890…87644651548075619839
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
1.817 × 10⁹⁷(98-digit number)
18170288113235020890…87644651548075619841
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
3.634 × 10⁹⁷(98-digit number)
36340576226470041781…75289303096151239679
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
3.634 × 10⁹⁷(98-digit number)
36340576226470041781…75289303096151239681
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
7.268 × 10⁹⁷(98-digit number)
72681152452940083562…50578606192302479359
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
7.268 × 10⁹⁷(98-digit number)
72681152452940083562…50578606192302479361
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
1.453 × 10⁹⁸(99-digit number)
14536230490588016712…01157212384604958719
Verify on FactorDB ↗Wolfram Alpha ↗
2^4 × origin + 1
1.453 × 10⁹⁸(99-digit number)
14536230490588016712…01157212384604958721
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.

View full Prime Chain Discovery page →
★★☆☆☆
Rarity
UncommonChain length 10
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
Verify on a Primecoin Node

Anyone running a Primecoin node can independently verify this block using the following RPC commands. Run these from the primecoin-cli command line or via the debug console in the Primecoin wallet.

1. Get block hash by height
getblockhash 706647

Returns the block hash for a given block height. Use this to confirm the hash shown above matches the chain.

2. Get full block data
getblock f4d51cfd86a6b7a6dde05ea90f86227e49227e0bfa71cd24e9478d6e90c5ff7a

Returns the full block header including difficulty, prime chain origin, prime chain type, transaction IDs, and all other fields shown on this page.

How to run these commands: To verify this data independently, open a terminal on your own Primecoin node and run primecoin-cli <command>. Alternatively, open the Primecoin-Qt wallet, go to Help → Debug Window → Console, and type the command directly. The node must be fully synced to this block height for the commands to return results.

Cross-reference on Chainz Explorer

Chainz is an independent Primecoin block explorer. Compare this block's data to verify accuracy.

View Block #706,647 on Chainz ↗
Circulating Supply:57,582,260 XPM·at block #6,792,286 · updates every 60s
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