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%I #27 Dec 15 2014 02:39:39
%S 9,9,3,5,3,2,0,0,0
%N Number of n-digit numbers N with distinct digits such that the reversal of N divides N.
%C Suggested by A214927.
%C a(n)=0 for all n > 6.
%e Solutions with 1 through 6 digits:
%e [1, 2, 3, 4, 5, 6, 7, 8, 9],
%e [10, 20, 30, 40, 50, 60, 70, 80, 90],
%e [510, 540, 810],
%e [5610, 5940, 8712, 8910, 9801],
%e [65340, 87120, 87912],
%e [659340, 879120],
%o (Python)
%o import collections
%o col = []
%o count = 0
%o for n in range(0,9):
%o ....a = 10**n
%o ....stop = 10**(n+1)
%o ....while a < stop:
%o ........b = str(a)
%o ........c = list(b)
%o ........d = c[::-1]
%o ........e = int("".join(c))
%o ........f = int("".join(d))
%o ........counter = collections.Counter(c)
%o ........if e % f == 0 and counter.most_common(1)[0][1] == 1:
%o ............count += 1
%o ............col.append(a)
%o ........a += 1
%o ....print(n+1," digits: ",count," elements: ",col)
%o ....count = 0
%o ....col = []
%o # _David Consiglio, Jr._, Dec 04 2014
%Y Cf. A214927, A222809, A222811, A222812.
%Y For the actual numbers see A223080.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, Mar 10 2013
%E a(8)-a(9) from _David Consiglio, Jr._, Dec 04 2014
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