Home/Chain Registry/Block #47,290

Block #47,290

1CCLength 8★☆☆☆☆

Cunningham Chain of the First Kind · Discovered 7/15/2013, 10:05:26 AM · Difficulty 8.8169 · 6,745,017 confirmations

1CC
Cunningham Chain of the First Kind

A sequence where each prime is double the previous prime plus one.

Block Header
Block Hash
57ef93491317ea4a2ff8da8f4930d280fac2b076a8e305762a17d6e6b42a049e

Height

#47,290

Difficulty

8.816920

Transactions

6

Size

1.94 KB

Version

2

Bits

08d121b0

Nonce

1,434

Timestamp

7/15/2013, 10:05:26 AM

Confirmations

6,745,017

Merkle Root

ce5a349898c288f1517e893c1a8ceda1fee72f66a1d12c41c9b20690e88eab72
Transactions (6)
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.

4.482 × 10⁹⁵(96-digit number)
44825008200114563104…41952146304909175800
Discovered Prime Numbers
p_k = 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.

1
origin − 1
4.482 × 10⁹⁵(96-digit number)
44825008200114563104…41952146304909175799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.965 × 10⁹⁵(96-digit number)
89650016400229126208…83904292609818351599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.793 × 10⁹⁶(97-digit number)
17930003280045825241…67808585219636703199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.586 × 10⁹⁶(97-digit number)
35860006560091650483…35617170439273406399
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
7.172 × 10⁹⁶(97-digit number)
71720013120183300966…71234340878546812799
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.434 × 10⁹⁷(98-digit number)
14344002624036660193…42468681757093625599
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.868 × 10⁹⁷(98-digit number)
28688005248073320386…84937363514187251199
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.737 × 10⁹⁷(98-digit number)
57376010496146640773…69874727028374502399
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 8 consecutive prime numbers forming a Cunningham Chain of the First Kind. 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
CommonChain length 8
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 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 47290

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 57ef93491317ea4a2ff8da8f4930d280fac2b076a8e305762a17d6e6b42a049e

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 #47,290 on Chainz ↗
Circulating Supply:57,582,422 XPM·at block #6,792,306 · updates every 60s
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