A309932 Distance from n to closest palindrome that is different from n.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 11, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 2, 1

Offset

0,12

Links

David A. Corneth, Table of n, a(n) for n = 0..9999

Index entries for sequences related to distance to nearest element of some set

Mathematica

a[n_] := Module[{k = 1}, While[! PalindromeQ[n + k] && ! PalindromeQ[n - k], k++]; k]; Table[a[n], {n, 0, 100}]

Prog

(PARI) a(n)={my(ispal=v->v==Vecrev(v)); for(k=1, oo, if(ispal(digits(n+k)) || ispal(digits(n-k)), return(k)))} \\ Andrew Howroyd, Aug 23 2019

Crossrefs

Cf. A002113, A100771.

Sequence in context: A125932 A175793 A244789 * A363968 A058886 A236858

Adjacent sequences: A309929 A309930 A309931 * A309933 A309934 A309935

Keyword

nonn,base,look

Author

Ilya Gutkovskiy, Aug 23 2019

Status

approved