A004726 Delete all 7's from the sequence of nonnegative integers.

0, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 1, 18, 19, 20, 21, 22, 23, 24, 25, 26, 2, 28, 29, 30, 31, 32, 33, 34, 35, 36, 3, 38, 39, 40, 41, 42, 43, 44, 45, 46, 4, 48, 49, 50, 51, 52, 53, 54, 55, 56, 5, 58, 59, 60, 61, 62, 63, 64, 65, 66, 6, 68, 69, 0, 1, 2

Offset

0,3

Links

Table of n, a(n) for n=0..71.

Prog

(Python)
def A004726(n):
    l = len(str(n))
    m = 7*(10**l-1)//9
    k = n + l - int(n+l < m)
    return 6 if k == m else int(str(k).replace('7', '')) # Chai Wah Wu, Apr 20 2021

Crossrefs

Cf. A004719, A004720, A004721, A004722, A004723, A004724, A004725, A004727, A004728.

Sequence in context: A194912 A194866 A345254 * A298747 A327105 A356451

Adjacent sequences: A004723 A004724 A004725 * A004727 A004728 A004729

Keyword

base,nonn

Author

N. J. A. Sloane

Status

approved