A007959 Some nontrivial permutation of digits is an odd number.

10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103

Offset: 1

Author

R. Muller

Keywords

• nonn
• base

Comments

Also: Odd numbers with more than 2 digits (so you can swap any two digits other than the last one), or numbers having at least one odd digit not in the last position (so you can swap that one with the last digit). - M. F. Hasler, Sep 30 2012

Examples

			The transposition (1,2) (nontrivial permutation of order two) acting on 11 yields the odd number 11. - _M. F. Hasler_, Sep 30 2012
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000
• F. Smarandache, Only Problems, Not Solutions!

Crossrefs

Cf. A007930.

Programs

Maple

filter:= proc(n) local L;
  L:= convert(n,base,10) mod 2;
  (L[1]=1 and nops(L) > 2) or max(L[2..-1])=1
end proc:
select(filter, [$10..1000]); # Robert Israel, Nov 21 2016

PARI

is_A007959(n)=bittest(n,0)&n>99 || while(n\=10, bittest(n,0) & return(1)) \\ M. F. Hasler, Sep 30 2012

Formula

a(n) ~ n. - Charles R Greathouse IV, Sep 19 2012