A091367 Primes p such that the sum of the digits raised to the 4th power is prime.
11, 23, 29, 41, 43, 47, 61, 67, 83, 89, 101, 113, 131, 179, 191, 197, 223, 269, 311, 313, 331, 353, 379, 397, 401, 443, 461, 601, 607, 641, 661, 719, 739, 809, 883, 911, 937, 971, 1013, 1019, 1031, 1033, 1091, 1097, 1103, 1109, 1181, 1301, 1303, 1367, 1433
Offset: 1
Examples
a(1) = 11 because 1^4 + 1^4 = 2 which is prime. a(10) = 89 because 8^4 + 9^4 = 10657 which is prime.
Links
- Michael S. Branicky, Table of n, a(n) for n = 1..10000
Crossrefs
Programs
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Mathematica
upto=500;Select[Prime[Range[upto]],PrimeQ[Total[IntegerDigits[#]^4]]&] (* Paolo Xausa, Nov 23 2021 *)
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Python
from sympy import isprime, primerange def ok(p): return isprime(sum(int(d)**4 for d in str(p))) def aupto(limit): return [p for p in primerange(1, limit+1) if ok(p)] print(aupto(1433)) # Michael S. Branicky, Nov 23 2021