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A255805
Numbers with no zeros in base-8 representation.
7
1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 62, 63, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84
OFFSET
1,2
COMMENTS
Different from A047592, A207481.
MATHEMATICA
Select[Range[100], DigitCount[#, 8, 0]==0&] (* Harvey P. Dale, Jun 08 2015 *)
PROG
(Haskell)
a255805 n = a255805_list !! (n-1)
a255805_list = iterate f 1 where
f x = 1 + if r < 7 then x else 8 * f x' where (x', r) = divMod x 8
(PARI) isok(m) = vecmin(digits(m, 8)) > 0; \\ Michel Marcus, Jan 23 2022
(Python)
def ok(n): return '0' not in oct(n)[2:]
print([k for k in range(85) if ok(k)]) # Michael S. Branicky, Jan 23 2022
CROSSREFS
Cf. A007094, A100970 (subsequence).
Zeroless numbers in some other bases <= 10: A000042 (base 2), A032924 (base 3), A023705 (base 4), A248910 (base 6), A255808 (base 9), A052382 (base 10).
Sequence in context: A207481 A047592 A187320 * A043093 A023802 A007915
KEYWORD
nonn,base,easy
AUTHOR
Reinhard Zumkeller, Mar 08 2015
STATUS
approved