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Some nontrivial permutation of digits gives an even number.
1

%I #17 Feb 19 2018 17:45:32

%S 20,21,22,23,24,25,26,27,28,29,40,41,42,43,44,45,46,47,48,49,60,61,62,

%T 63,64,65,66,67,68,69,80,81,82,83,84,85,86,87,88,89,100,101,102,103,

%U 104,105,106,107,108,109,110,112,114,116,118,120,121,122,123,124,125,126,127,128,129,130

%N Some nontrivial permutation of digits gives an even number.

%C Also: Even numbers with more than 2 digits (so you can swap any two digits other than the last one), or numbers having at least one even digit not in the last position (so you can swap that one with the last digit). - _M. F. Hasler_, Sep 30 2012

%H F. Smarandache, <a href="http://www.gallup.unm.edu/~smarandache/OPNS.pdf">Only Problems, Not Solutions!</a>

%F a(n) ~ n. - _Charles R Greathouse IV_, Sep 19 2012

%e 22 is a term since the permutation that swaps the first and second digits gives an even number. - _N. J. A. Sloane_, Sep 30 2012

%o (PARI) is_A007930(n)={!bittest(n, 0) & n>99 || while(n\=10, bittest(n, 0) || return(1))} \\ - _M. F. Hasler_, Sep 30 2012

%Y Cf. A007959.

%K nonn,base

%O 1,1

%A R. Muller

%E Missing terms 112, 114, 116, 118 added by _Sean A. Irvine_, Feb 19 2018