A109841 a(n) is the minimal j >= n such that the sum of consecutive integers from n to j is a palindrome.

1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 11, 45, 24, 19, 18, 17, 27, 29, 34, 26, 23, 22, 30, 32, 43, 31, 28, 35, 40, 44, 44, 34, 33, 45, 56, 38, 106, 39, 49, 61, 73, 50, 58, 44, 56, 48, 54, 53, 50, 51, 60, 59, 58, 57, 55, 58, 64, 63, 62, 61, 69, 72, 68, 67, 66, 66, 79, 100, 72, 71, 83, 78

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

a(14)=19 because 14 + 15 + 16 + 17 + 18 + 19 = 99.

Mathematica

sci[n_]:=Module[{k=n}, While[!PalindromeQ[Total[Range[n, k]]], k++]; k]; Array[sci, 80] (* Harvey P. Dale, Jul 03 2023 *)

Crossrefs

Cf. A109842.

Sequence in context: A248899 A029970 A143265 * A174234 A163807 A118766

Adjacent sequences: A109838 A109839 A109840 * A109842 A109843 A109844

Keyword

base,easy,nonn

Author

Jason Earls, Jul 05 2005

Status

approved