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A037440
Positive numbers having the same set of digits in base 7 and base 10.
3
1, 2, 3, 4, 5, 6, 23, 46, 265, 316, 1030, 1234, 1336, 1366, 1401, 1431, 1443, 1454, 1464, 2060, 2116, 3261, 3515, 3621, 4631, 5052, 10144, 10342, 10542, 11134, 11425, 11524, 11544, 12415, 12450, 12532, 12564, 12651, 13035, 13045, 13245
OFFSET
1,2
EXAMPLE
1336 is in the sequence because 1336 in base 7 is 3616.
MATHEMATICA
Select[Range@ 13300, Union@ IntegerDigits@ # == Union@ IntegerDigits[#, 7] &] (* Michael De Vlieger, Feb 18 2017 *)
PROG
(PARI) isok(n) = Set(digits(n, 7)) == Set(digits(n)); \\ Michel Marcus, Feb 18 2017
(Python)
from sympy.ntheory import digits
def ok(n): return set(map(int, str(n))) == set(digits(n, 7)[1:])
print([k for k in range(1, 10**6) if ok(k)]) # Michael S. Branicky, Apr 22 2023
CROSSREFS
Subsequence of A037404.
Cf. A007093.
Sequence in context: A183529 A342999 A037404 * A130604 A359224 A262434
KEYWORD
nonn,base
EXTENSIONS
More terms from Don Reble, Apr 28 2006
Edited by John Cerkan, Feb 17 2017
STATUS
approved