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.

A251623 Primes p with property that the sum of the 4th powers of the successive gaps between primes <= p is a prime number.

Original entry on oeis.org

5, 19, 29, 41, 61, 67, 83, 89, 103, 113, 167, 179, 229, 263, 281, 283, 307, 317, 359, 461, 467, 509, 563, 571, 613, 739, 743, 761, 1019, 1031, 1051, 1093, 1229, 1291, 1297, 1319, 1409, 1447, 1609, 1621, 1667, 1747, 1801, 1877, 1979, 2113, 2137, 2161
Offset: 1

Views

Author

Abhiram R Devesh, Dec 06 2014

Keywords

Examples

			a(1)=5; primes less than or equal to 5: [2, 3, 5]; 4th power of prime gaps: [1, 16]; sum of 4th power of prime gaps: 17.
a(2)=19; primes less than or equal to 13: [2, 3, 5, 7, 11, 13, 17, 19]; 4th powers of prime gaps (see A140299): [1, 16, 16, 256, 16, 256, 16]; sum of these: 577.
		

Crossrefs

Cf. A006512 (with gaps), A247177 (with squares of gaps), A247178 (with cubes of gaps).

Programs

  • Mathematica
    p = 2; q = 3; s = 0; lst = {}; While[p < 2500, s = s + (q - p)^4; If[ PrimeQ@ s, AppendTo[lst, q]]; p = q; q = NextPrime@ q]; lst (* Robert G. Wilson v, Dec 19 2014 *)
  • PARI
    p = 2; q = 3; s = 1; for (i = 1, 100, p = q; q = nextprime (q + 1); if (isprime (s = s + (q - p)^4), print1 (q ", "))) \\ Zak Seidov, Jan 19 2015
  • Python
    import sympy
    p=2
    s=0
    while 10000>p>0:
        np=sympy.nextprime(p)
        if sympy.isprime(s):
            print(p)
        d=np-p
        s+=(d**4)
        p=np