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 A222810 Number of n-digit numbers N with distinct digits such that the reversal of N divides N. 7
 9, 9, 3, 5, 3, 2, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Suggested by A214927. a(n)=0 for all n > 6. LINKS EXAMPLE Solutions with 1 through 6 digits: [1, 2, 3, 4, 5, 6, 7, 8, 9], [10, 20, 30, 40, 50, 60, 70, 80, 90], [510, 540, 810], [5610, 5940, 8712, 8910, 9801], [65340, 87120, 87912], [659340, 879120], PROG (Python) import collections col = [] count = 0 for n in range(0, 9): ....a = 10**n ....stop = 10**(n+1) ....while a < stop: ........b = str(a) ........c = list(b) ........d = c[::-1] ........e = int("".join(c)) ........f = int("".join(d)) ........counter = collections.Counter(c) ........if e % f == 0 and counter.most_common(1)[0][1] == 1: ............count += 1 ............col.append(a) ........a += 1 ....print(n+1, " digits: ", count, " elements: ", col) ....count = 0 ....col = [] # David Consiglio, Jr., Dec 04 2014 CROSSREFS Cf. A214927, A222809, A222811, A222812. For the actual numbers see A223080. Sequence in context: A074879 A291366 A146490 * A140416 A226204 A296454 Adjacent sequences:  A222807 A222808 A222809 * A222811 A222812 A222813 KEYWORD nonn,base AUTHOR N. J. A. Sloane, Mar 10 2013 EXTENSIONS a(8)-a(9) from David Consiglio, Jr., Dec 04 2014 STATUS approved

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Last modified December 5 22:37 EST 2019. Contains 329782 sequences. (Running on oeis4.)