cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A091367 Primes p such that the sum of the digits raised to the 4th power is prime.

Original entry on oeis.org

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

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Author

Chuck Seggelin, Jan 03 2004

Keywords

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.
		

Crossrefs

Cf. A046704 (primes whose digits sum to a prime), A052034 (primes whose digits squared sum to a prime), A091366 (primes whose digits cubed sum to a prime).

Programs

  • Mathematica
    upto=500;Select[Prime[Range[upto]],PrimeQ[Total[IntegerDigits[#]^4]]&] (* Paolo Xausa, Nov 23 2021 *)
  • 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