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

Author

Rémy Sigrist, Dec 28 2024

Keywords

• nonn
• base

Comments

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

Examples

			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
		

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

Crossrefs

See A233571 for a similar sequence.

Cf. A379015, A379040.

Programs

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; }