A178493 Numbers of powers of phi in base-phi expansion of phi-antipalindromic numbers (A178482).

1, 2, 3, 2, 3, 4, 5, 2, 3, 4, 5, 4, 5, 6, 7, 2, 3, 4, 5, 4, 5, 6, 7, 4, 5, 6, 7, 6, 7, 8, 9, 2, 3, 4, 5, 4, 5, 6, 7, 4, 5, 6, 7, 6, 7, 8, 9, 4, 5, 6, 7, 6, 7, 8, 9, 6, 7, 8, 9, 8, 9, 10, 11, 2, 3, 4, 5, 4, 5, 6, 7, 4, 5, 6, 7, 6, 7, 8, 9, 4, 5, 6, 7, 6, 7, 8

Offset: 1

Author

Vladimir Shevelev, May 28 2010, May 30 2010

Keywords

• nonn
• base

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from T. D. Noe)
• Eric Weisstein's World of Mathematics, Phi Number System

Crossrefs

Cf. A178482, A005248, A055778, A104605, A104626, A104627, A104628.

Programs

Mathematica

powNum[1] = 1; powNum[n_] := Module[{d = RealDigits[n, GoldenRatio, 2*Ceiling[Log[GoldenRatio, n]]]}, e = d[[2]] - Flatten @ Position[d[[1]], 1]; If[Reverse[e] == -e, Length[e], 0]]; Select[Array[powNum, 400], # > 0 &] (* Amiram Eldar, Apr 23 2020 *)

Extensions

Extended by T. D. Noe, May 20 2011