cp's OEIS Frontend

A217657 Delete the initial digit in decimal representation of n.

%I A217657 #24 Jul 01 2022 22:10:38
%S A217657 0,0,0,0,0,0,0,0,0,0,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,
%T A217657 4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,
%U A217657 8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20
%N A217657 Delete the initial digit in decimal representation of n.
%C A217657 When n - a(n)*10^[log_10 n] >= 10^[(log_10 n) - 1], where [] denotes floor, or when n < 100 and 10|n, n is the concatenation of A000030(n) and a(n) - corrected by _Glen Whitney_, Jul 01 2022
%C A217657 a(110) = 10 is the first term > 9. The sequence consists of 10 repetitions of 0 (n = 0..9), then 9 repetitions of {0, ..., 9} (n = 10..99), then 9 repetitions of {0, ..., 99} (n = 100..999), and so on. - _M. F. Hasler_, Oct 18 2017
%H A217657 Reinhard Zumkeller, <a href="/A217657/b217657.txt">Table of n, a(n) for n = 0..10000</a>
%F A217657 a(n) = 0 if n <= 9, otherwise 10*a(floor(n/10)) + n mod 10.
%F A217657 a(n) = n mod 10^floor(log_10(n)), a(0) = 0. - _M. F. Hasler_, Oct 18 2017
%t A217657 Array[FromDigits@ Rest@ IntegerDigits@ # &, 121, 0] (* _Michael De Vlieger_, Dec 22 2019 *)
%o A217657 (Haskell)
%o A217657 a217657 n | n <= 9    = 0
%o A217657           | otherwise = 10 * a217657 n' + m where (n', m) = divMod n 10
%o A217657 (PARI) apply( A217657(n)=n%10^logint(n+!n,10), [0..199]) \\ _M. F. Hasler_, Oct 18 2017, edited Dec 22 2019
%o A217657 (Python)
%o A217657 def a(n): return 0 if n < 10 else int(str(n)[1:])
%o A217657 print([a(n) for n in range(121)]) # _Michael S. Branicky_, Jul 01 2022
%Y A217657 Cf. A059995 (drop final digit of n), A000030 (initial digit of n), A202262.
%K A217657 nonn,base,look
%O A217657 0,13
%A A217657 _Reinhard Zumkeller_, Oct 10 2012
%E A217657 Data extended to include the first terms larger than 9, by _M. F. Hasler_, Dec 22 2019