A238893 Encoded bases for which A214425(n) is palindromic.

179, 238, 135, 268, 359, 137, 137, 258, 136, 268, 237, 578, 268, 567, 589, 137, 257, 367, 269, 138, 136, 138, 489, 679, 678, 137, 268, 137, 268, 178, 179, 289, 135, 258, 147, 137, 137, 137, 128, 268, 137, 137, 268, 137, 137, 137, 137, 248, 139, 259, 137

Offset

1,1

Comments

The three bases b < c < d are encoded as one number (b-1)*100 + (c-1)*10 + (d-1). Similar to A214427 which tabulates the single base for which A214423(n) is palindromic. The vast majority of these palindromes are for the three bases (2,4,8), which encodes as 137 in this sequence.

Links

T. D. Noe, Table of n, a(n) for n = 1..1234

Example

A214425(1) = 9. The number 9 is palindromic in 3 bases: 2, 8, and 10. Hence, a(1) = 179.

Mathematica

n = -1; t = {}; While[Length[t] < 51, n++; If[Count[c = Table[s = IntegerDigits[n, m]; s == Reverse[s], {m, 2, 10}], True] == 3, d = Flatten[Position[c, True]]; AppendTo[t, 100*d[[1]] + 10*d[[2]] + d[[3]]]]]; t

Crossrefs

Cf. A214423, A214425, A214427, A238338.

Sequence in context: A217550 A226928 A162164 * A230809 A335067 A142028

Adjacent sequences: A238890 A238891 A238892 * A238894 A238895 A238896

Keyword

nonn,base

Author

T. D. Noe, Mar 07 2014

Status

approved