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%I #11 Dec 08 2018 02:41:55
%S 11,12,15,21,22,24,25,31,32,33,35,36,41,42,44,45,48,51,52,55,61,62,63,
%T 64,65,66,71,72,75,77,81,82,84,85,88,91,92,93,95,96,99,101,102,104,
%U 105,125,201,202,204,205,208,225,301,302,303,304,305,306,312,315,325,375,401,402,404,405,408,416,425,501
%N Numbers divisible by themselves with first digit removed (A217657), excluding multiples of 10.
%C Obviously, any term multiplied by 10 would again be a term, so we exclude trailing zeros.
%C This sequence cannot contain single-digit numbers (which would yield 0 with the initial digit removed), in contrast to A178158 (numbers divisible by every suffix of n) where the condition is vacuously satisfied for single-digit numbers.
%C 416 is the first term in the present sequence which is not in A178158.
%C See A292684 and A292685 for the (number of) multiples of N = a(n) which have the same property and yield the same ratio N/A217657(N).
%e 12 is in the sequence because it is divisible by 2.
%e 416 is in the sequence because it is divisible by 16, 416 = 4*4*25 + 16.
%t fQ[n_] := Mod[n, 10] > 0 && Mod[n, n - Quotient[n, 10^Floor@ Log10@ n] 10^Floor@ Log10@ n] == 0; Select[ Range[11, 501], fQ] (* _Robert G. Wilson v_, Oct 18 2017 *)
%o (PARI) select( is(n)=n%10&&(m=n%10^logint(n,10))&&!(n%m), [0..500])
%Y Cf. A217657, A178158, A034709.
%Y Cf. A292684, A292685.
%K nonn,base
%O 1,1
%A _M. F. Hasler_, Oct 17 2017
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