A085574 Least k such that n*(n+1)*(n+2) + k is palindromic.

0, 9, 6, 1, 2, 7, 1, 7, 9, 11, 55, 38, 42, 83, 34, 98, 71, 46, 17, 99, 75, 77, 31, 51, 21, 35, 98, 82, 102, 32, 87, 49, 23, 84, 44, 89, 11, 15, 86, 6, 1, 33, 18, 39, 89, 625, 567, 111, 571, 731, 585, 17, 341, 341, 11, 445, 537, 182, 672, 802, 566, 68, 182, 1012, 352, 407

Offset

1,2

Comments

Conjecture: For all n > 108, a(n) is > 1.

Links

Table of n, a(n) for n=1..66.

Erich Friedman, Palindromic Problem #2.

Example

a(2)=9 because 2*3*4+9 = 33.

Mathematica

lk[n_]:=Module[{t=n(n+1)(n+2), k=1}, While[IntegerDigits[t+k]!=Reverse[ IntegerDigits[ t+k]], k++]; k]; Join[{0}, Array[lk, 70, 2]] (* Harvey P. Dale, Oct 23 2015 *)

Crossrefs

Sequence in context: A020783 A075567 A019883 * A194825 A092732 A342680

Adjacent sequences: A085571 A085572 A085573 * A085575 A085576 A085577

Keyword

base,nonn

Author

Jason Earls, Jul 06 2003

Status

approved