A377625 Nonnegative numbers whose nonadjacent form is antipalindromic.

0, 3, 7, 15, 31, 51, 63, 75, 99, 127, 155, 195, 231, 255, 279, 315, 387, 455, 511, 567, 635, 723, 771, 819, 903, 975, 1023, 1071, 1143, 1227, 1275, 1323, 1427, 1539, 1651, 1799, 1935, 2047, 2159, 2295, 2443, 2555, 2667, 2835, 2979, 3075, 3171, 3315, 3495, 3591

Offset

1,2

Comments

Also nonnegative numbers k such that A379015(k) = -k.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Joerg Arndt, Matters Computational (The Fxtbook), pages 61-62.

Wikipedia, Non-adjacent form

Example

The first terms, alongside their nonadjacent forms, are:
  n   a(n)  naf(a(n))
  --  ----  ----------
   1     0           0
   2     3         10T
   3     7        100T
   4    15       1000T
   5    31      10000T
   6    51     10T010T
   7    63     100000T
   8    75     1010T0T
   9    99    10T0010T
  10   127    1000000T
  11   155    10100T0T
  12   195   10T00010T
  13   231   100T0100T
  14   255   10000000T
  15   279   10010T00T
  16   315   101000T0T

Prog

(PARI) is(n) = { my (m = 0, d, r = n); while (r, m *= 2; if (r % 2, r -= d = 2 - (r % 4); m += d; ); r \= 2; ); m == -n; }

Crossrefs

See A233571 for a similar sequence.

Cf. A379015, A379040.

Sequence in context: A043729 A331503 A137170 * A222813 A304078 A151338

Adjacent sequences: A377622 A377623 A377624 * A377626 A377627 A377628

Keyword

nonn,base

Author

Rémy Sigrist, Dec 28 2024

Status

approved