A067031 Numbers that are not of the form k + reverse(k) for any k.

1, 3, 5, 7, 9, 13, 15, 17, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87

Offset

0,2

Links

Daniel Starodubtsev, Table of n, a(n) for n = 0..10000

Example

3 belongs to the sequence since there is no k such that k + reverse(k) = 3.

Mathematica

Module[{nn=100, rd}, rd=Union[Table[n+FromDigits[ Reverse[ IntegerDigits[ n]]], {n, nn}]]; Complement[Range[nn], rd]] (* Harvey P. Dale, Dec 16 2013 *)

Prog

(ARIBAS): function a067031(a, b: integer); var k, n, i, rev: integer; test: boolean; st, nst: string; begin for n := a to b do k := 0; test := 1; while test and k <= n do st := itoa(k); nst := ""; for i := 0 to length(st) - 1 do nst := concat(st[i], nst); end; rev := atoi(nst); if n = k + rev then test := 0; else inc(k); end; end; if k > n then write(n, ", "); end; end; end; a067031(0, 100); .

Crossrefs

Cf. A056964.

Complement of A067030.

Cf. A033865, A067030, A067032, A067033, A067034.

Sequence in context: A245212 A063081 A337431 * A204454 A029740 A063425

Adjacent sequences: A067028 A067029 A067030 * A067032 A067033 A067034

Keyword

base,easy,nonn

Author

Klaus Brockhaus, Dec 29 2001

Status

approved