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A067031
Numbers that are not of the form k + reverse(k) for any k.
19
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
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.
Sequence in context: A245212 A063081 A337431 * A204454 A029740 A063425
KEYWORD
base,easy,nonn
AUTHOR
Klaus Brockhaus, Dec 29 2001
STATUS
approved