Block #3,506,246

1CCLength 10★★☆☆☆

Cunningham Chain of the First Kind · Discovered 1/9/2020, 4:47:33 AM · Difficulty 10.9304 · 3,334,216 confirmations

1CC
Cunningham Chain of the First Kind

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

Block Header
Block Hash
65c4a074dd584cea20ec0076a6e9fb64d2abb4131c30323c2c568aeca681061a

Height

#3,506,246

Difficulty

10.930398

Transactions

7

Size

43.82 KB

Version

2

Bits

0aee2e91

Nonce

146,332,895

Timestamp

1/9/2020, 4:47:33 AM

Confirmations

3,334,216

Merkle Root

673dd0f2e8f06b175e4d259c81e869434522855ef995e1b96eb2e2d267507ac4
Transactions (7)
1 in → 1 out8.8400 XPM110 B
50 in → 1 out100.0973 XPM7.28 KB
50 in → 1 out100.0912 XPM7.27 KB
50 in → 1 out100.1037 XPM7.26 KB
50 in → 1 out100.0789 XPM7.27 KB
50 in → 1 out100.1223 XPM7.26 KB
50 in → 1 out100.1096 XPM7.27 KB
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.

4.005 × 10⁹³(94-digit number)
40050544728573152878…95863076402641998279
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
4.005 × 10⁹³(94-digit number)
40050544728573152878…95863076402641998279
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
2
2^1 × origin − 1
8.010 × 10⁹³(94-digit number)
80101089457146305757…91726152805283996559
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
3
2^2 × origin − 1
1.602 × 10⁹⁴(95-digit number)
16020217891429261151…83452305610567993119
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
4
2^3 × origin − 1
3.204 × 10⁹⁴(95-digit number)
32040435782858522302…66904611221135986239
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
5
2^4 × origin − 1
6.408 × 10⁹⁴(95-digit number)
64080871565717044605…33809222442271972479
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
6
2^5 × origin − 1
1.281 × 10⁹⁵(96-digit number)
12816174313143408921…67618444884543944959
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
7
2^6 × origin − 1
2.563 × 10⁹⁵(96-digit number)
25632348626286817842…35236889769087889919
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
8
2^7 × origin − 1
5.126 × 10⁹⁵(96-digit number)
51264697252573635684…70473779538175779839
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
9
2^8 × origin − 1
1.025 × 10⁹⁶(97-digit number)
10252939450514727136…40947559076351559679
Verify on FactorDB ↗Wolfram Alpha ↗
×2+1 →
10
2^9 × origin − 1
2.050 × 10⁹⁶(97-digit number)
20505878901029454273…81895118152703119359
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 10 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.

★★☆☆☆
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 1CC formula:

1CC: p₁ (first prime), p₂ = 2p₁ + 1, p₃ = 2p₂ + 1, …
Circulating Supply:57,968,024 XPM·at block #6,840,461 · 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.
Privacy Policy·

Cookie Preferences

We use cookies to enhance your experience. Some are essential for the site to function, while others help us understand how you use the site.

·Privacy Policy