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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
OFFSET
1,1
COMMENTS
Suggested by A214927.
a(n)=0 for all n > 6.
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
For the actual numbers see A223080.
Sequence in context: A074879 A291366 A146490 * A140416 A340628 A226204
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