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%I #16 Sep 24 2018 16:53:14
%S 1,2,3,4,5,7,8,9,10,11,13,14,15,16,17,19,22,23,25,26,29,31,32,33,34,
%T 35,37,38,39,41,43,44,46,47,49,50,51,52,53,55,57,58,59,61,62,64,67,68,
%U 71,73,74,75,76,77,79,83,85,86,89,91,92,93,94,95,97,98,99,101,103,105,106
%N Deficient numbers whose reversal is also a deficient number.
%H Ivan Neretin, <a href="/A098767/b098767.txt">Table of n, a(n) for n = 1..10000</a>
%e a(12)=14 because 14 and reverse of 14, i.e., 41, are deficient numbers.
%e a(13)=15 because 15 is a deficient number which on reversing its digits also gives a deficient number, i.e., 51.
%t Select[Range@106, DivisorSigma[1, #] < 2 # && DivisorSigma[1, n = FromDigits@Reverse@IntegerDigits@#] < 2 n &] (* _Ivan Neretin_, Dec 19 2015 *)
%o (PARI) isdefic(n) = (sigma(n) < 2*n);
%o isok(n) = isdefic(n) && isdefic(eval(concat(Vecrev(Str(n))))); \\ _Michel Marcus_, Dec 20 2015
%Y Cf. A005100.
%K easy,nonn,base
%O 1,2
%A _Shyam Sunder Gupta_, Oct 02 2004
%E Edited by _N. J. A. Sloane_ at the suggestion of _Andrew S. Plewe_, Jun 11 2007
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