# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a331492 Showing 1-1 of 1 %I A331492 #8 Jan 18 2020 18:55:29 %S A331492 0,1,17,315,316,5623,99999,100000,1778279,31622776,562341324, %T A331492 562341325,9999999999,10000000000,177827941003,3162277660168, %U A331492 56234132519034,999999999999999,1000000000000000,17782794100389227,17782794100389228,316227766016837932,316227766016837933 %N A331492 Numbers k such that the digits of k^(1/5) begin with k. %C A331492 The following algorithm will generate all numbers k such that the digits of k^(1/b) begins with k: For each integer m >= 0, compute r = floor(10^(bm/(b-1)). Let s <= r be the largest integer >= 0 such that (r-s)*10^(bm) < (r-s+1)^b. Then r, r-1, ... r-s are such numbers k and there are no other such numbers. %H A331492 Chai Wah Wu, Table of n, a(n) for n = 1..1140 %e A331492 5623^(1/5) = 5.6233305990931... which starts with the digits 5623, so 5623 is in the sequence. %Y A331492 Cf. A307371, A307588, A307600. %K A331492 nonn,base %O A331492 1,3 %A A331492 _Chai Wah Wu_, Jan 18 2020 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE