

A236366


Numbers such that their digits indicate bases k , 2 <= k <= 9, in which representation of n is palindrome; a(n)=0, if there is no such a base.


1



23456789, 3456789, 2456789, 356789, 246789, 5789, 2689, 379, 28, 349, 0, 5, 3, 6, 24, 37, 24, 58, 0, 39, 246, 0, 3, 57, 4, 35, 28, 36, 4, 9, 25, 7, 2, 4, 6, 58, 6, 4, 0, 379, 5, 4, 6, 0, 28, 45, 0, 7, 6, 79, 24, 35, 0, 8, 46, 3, 57, 0, 4, 9, 6, 5, 248, 7, 248
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OFFSET

1,1


LINKS

Peter J. C. Moses, Table of n, a(n) for n = 1..5000


EXAMPLE

Let n=29. In base 2,3,...,9 the representations of 29 are 11101, 1002, 131, 104, 45, 41, 35, 32. In this list only 131 (base4) is palindrome. Thus a(29)=4.


MATHEMATICA

Table[FromDigits[1+Flatten[Position[Map[Reverse[#]==#&, Map[IntegerDigits[n, #]&, Range[2, 9]]], True]]], {n, 50}]


CROSSREFS

Cf. A002113, A235922.
Sequence in context: A183736 A105238 A252396 * A097617 A160402 A243364
Adjacent sequences: A236363 A236364 A236365 * A236367 A236368 A236369


KEYWORD

nonn,base


AUTHOR

Vladimir Shevelev, Jan 23 2014


STATUS

approved



