[go: up one dir, main page]

login
A037474
a(n) = Sum{d(i)*8^i: i=0,1,...,m}, where Sum{d(i)*7^i: i=0,1,...,m} is the base 7 representation of n.
14
0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84, 85
OFFSET
0,3
COMMENTS
Numbers without digit 7 in base 8. Complement of A337239. - François Marques, Oct 13 2020
LINKS
François Marques, Table of n, a(n) for n = 0..10000 (first 1000 terms from Clark Kimberling)
EXAMPLE
a(48)=54 because 48 is 66_7 in base 7 and 66_8=54. - François Marques, Oct 13 2020
MATHEMATICA
Table[FromDigits[RealDigits[n, 7], 8], {n, 0, 100}] (* Clark Kimberling, Aug 14 2012 *)
PROG
(PARI) a(n) = fromdigits(digits(n, 7), 8); \\ François Marques, Oct 13 2020
(Python)
from gmpy2 import digits
def A037474(n): return int(digits(n, 7), 8) # Chai Wah Wu, Dec 04 2024
CROSSREFS
Cf. Numbers with at least one digit b-1 in base b : A074940 (b=3), A337250 (b=4), A337572 (b=5), A333656 (b=6), A337141 (b=7), A337239 (b=8), A338090 (b=9), A011539 (b=10), A095778 (b=11).
Cf. Numbers with no digit b-1 in base b: A005836 (b=3), A023717 (b=4), A020654 (b=5), A037465 (b=6), A020657 (b=7), this sequence (b=8), A037477 (b=9), A007095 (b=10), A171397 (b=11).
Sequence in context: A047421 A004777 A059561 * A292638 A000378 A335513
KEYWORD
nonn,base,easy
EXTENSIONS
Offset changed to 0 by Clark Kimberling, Aug 14 2012
STATUS
approved