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Delete all 8's from the sequence of nonnegative integers.
9

%I #18 Apr 22 2021 22:09:37

%S 0,1,2,3,4,5,6,7,9,10,11,12,13,14,15,16,17,1,19,20,21,22,23,24,25,26,

%T 27,2,29,30,31,32,33,34,35,36,37,3,39,40,41,42,43,44,45,46,47,4,49,50,

%U 51,52,53,54,55,56,57,5,59,60,61,62,63,64,65,66,67,6,69,70,71

%N Delete all 8's from the sequence of nonnegative integers.

%o (Python)

%o def A004727(n):

%o l = len(str(n))

%o m = 8*(10**l-1)//9

%o k = n + l - int(n+l < m)

%o return 7 if k == m else int(str(k).replace('8','')) # _Chai Wah Wu_, Apr 20 2021

%Y Cf. A004719, A004720, A004721, A004722, A004723, A004724, A004725, A004726, A004728.

%K base,nonn

%O 0,3

%A _N. J. A. Sloane_