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A236673
Exponents of powers of 3 that contain all ten decimal digits.
5
39, 45, 47, 48, 53, 57, 60, 61, 62, 63, 64, 65, 67, 69, 70, 71, 72, 73, 74, 76, 77, 78, 79, 80, 82, 83, 85, 86, 87, 88, 89, 90, 92, 93, 94, 95, 96, 97, 98, 99, 102, 103, 105, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123
OFFSET
1,1
COMMENTS
It is conjectured that after a(43), a(n) = n + 63 (i.e., natural numbers beginning with 107).
Complement of A236674.
LINKS
EXAMPLE
3^53 = 19383245667680019896796723, which contains two 1's, two 2's, three 3's, one 4, one 5, five 6's, three 7's, three 8's, four 9's and two 0's, so 53 is in the sequence.
3^57 = 1570042899082081611640534563, which contains four 1's, two 2's, two 3's, three 4's, three 5's, three 6's, one 7, three 8's, two 9's and five 0's.
58 is not in the sequence because there are no 5's in 3^58 = 4710128697246244834921603689.
MATHEMATICA
Select[Range[0, 200], Union[IntegerDigits[3^#]] == Range[0, 9] &] (* T. D. Noe, Jan 29 2014 *)
PROG
(Python)
def PanDig(x):
..a = '1234567890'
..for n in range(10**3):
....count = 0
....for i in a:
......if str(x**n).count(i) > 0:
........count += 1
......else:
........break
....if count == len(a):
......print(n)
CROSSREFS
Sequence in context: A261374 A309696 A061756 * A119028 A252712 A252711
KEYWORD
nonn,base
AUTHOR
Derek Orr, Jan 29 2014
STATUS
approved