This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A018160 #14 Jul 08 2025 06:29:44 %S A018160 1,2,3,5,9,16,28,49,84,147,256,446,776,1351,2353,4096,7132,12417, %T A018160 21619,37641,65536,114105,198668,345901,602249,1048576,1825677, %U A018160 3178688,5534417,9635980,16777216,29210830,50859008 %N A018160 Powers of fifth root of 16 rounded to nearest integer. %t A018160 Floor[(16^(1/5))^Range[0,40]+1/2] (* _Harvey P. Dale_, May 23 2012 *) %o A018160 (Python) %o A018160 from gmpy2 import iroot_rem %o A018160 def A018160(n): %o A018160 i, j = iroot_rem(1<<(n<<2),5) %o A018160 return int(i)+int(j<<5>=10*i*((i*((i*(i+1)<<1)+1)<<2)+1)+1) # _Chai Wah Wu_, Jun 20 2024 %Y A018160 Cf. A011101. %K A018160 nonn %O A018160 0,2 %A A018160 _N. J. A. Sloane_