A072497 Numbers k such that k^2 is a member of A072498.

2, 3, 4, 5, 6, 7, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78

Offset

1,1

Comments

p^m are members of the sequence, where p is prime and m different from k(4k-1) and k(4k+1) (spatially all primes, p^1).

Complement of A072327 in the positive integers. - Robert Israel, Dec 10 2024

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= proc(n) local s, F, d, p;
  s:= n^2;
  F:= sort(convert(numtheory:-divisors(s), list));
  p:= 1:
  for d in F do
    p:= p*d;
    if p > s then return true
    elif p = s then return false
    fi
  od;
end proc:
select(filter, [$1..100]); # Robert Israel, Dec 10 2024

Crossrefs

Cf. A072498, A072327, A072510.

Sequence in context: A294295 A191852 A136416 * A300064 A039217 A239289

Adjacent sequences: A072494 A072495 A072496 * A072498 A072499 A072500

Keyword

nonn

Author

Vladimir Baltic, Aug 04 2002

Status

approved