A275419 Representable integers n that are not the inverse of their inverse in binary64 (double precision) IEEE 754 floating-point arithmetic (Version where n and 1/(1/n) are unequal).

49, 93, 98, 99, 103, 105, 107, 117, 123, 186, 196, 197, 198, 206, 210, 211, 214, 221, 227, 234, 237, 239, 243, 245, 246, 249, 253, 372, 391, 392, 393, 394, 396, 412, 415, 417, 420, 422, 425, 428, 442, 443, 445, 454, 459, 468, 474, 478, 479, 483, 486, 489, 490, 491, 492, 497, 498, 499, 501

Offset: 1

Author

Julien Freslon, Jul 27 2016

Keywords

• nonn
• base
• fini
• less

Comments

Note that n*(1/n) and 1 are unequal for a different integer sequence.

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Programs

C

int is(int n) {
  double d = n;
  double di = 1/d;
  return 1/di != d;
} /* Charles R Greathouse IV, Jul 29 2016 */