A396248
Primes prime(k) such that prime(k) - prime(k-1) is a factorial.
The sequence consists of all primes prime(k) for which the gap to the previous prime prime(k-1) is a factorial.Every upper member of a twin prime (A006512) pair belongs to the sequence, since 2 = 2!.
Sequence Chart
Data
3,5,7,13,19,29,31,37,43,53,59,61,67,73,79,89,103,109,137,139,151,157,163,173,179,181,193,199,229,239,241,257,263,269,271,277,283,313,337,349,359,373,379,389,421,433,439,449,463,509,523,547,563,569,571,577
Computational Implementations
PYTHON
from sympy import prime
import math
def sequence(n_max):
results = []
facts = [math.factorial(k) for k in range(0, 7)]
for i in range(2, n_max + 1):
gap = prime(i) - prime(i-1)
if gap in facts:
results.append(prime(i))
return results
print(sequence(200)) Mathematica
seq[lim_] := Module[{ps = Select[Range[lim], PrimeQ], f = 1, k = 1, d, mxd}, d = Differences[ps]; mxd = Max[d]; While[f < mxd, k++; f *= k]; ps[[1 + Position[d, _?(MemberQ[Range[k]!, #] &)] // Flatten]]]; seq[600] (* _Amiram Eldar_, May 22 2026 *) Cross-References
See also OEIS entries: Cf. A000142, A031925, A126720, A192434, A001223, A000040, A006512.