cp's OEIS Frontend

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.

A018133 Powers of fifth root of 7 rounded to nearest integer.

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%I A018133 #16 Jul 08 2025 06:28:05
%S A018133 1,1,2,3,5,7,10,15,22,33,49,72,107,157,232,343,506,747,1102,1627,2401,
%T A018133 3543,5229,7717,11389,16807,24803,36604,54019,79720,117649,173623,
%U A018133 256229,378135,558042,823543
%N A018133 Powers of fifth root of 7 rounded to nearest integer.
%t A018133 Round[Surd[7,5]^Range[0,40]] (* _Harvey P. Dale_, Jul 27 2021 *)
%o A018133 (Python)
%o A018133 from gmpy2 import iroot_rem
%o A018133 def A018133(n):
%o A018133     i, j = iroot_rem(7**n,5)
%o A018133     return int(i)+int(j<<5>=10*i*((i*((i*(i+1)<<1)+1)<<2)+1)+1) # _Chai Wah Wu_, Jun 20 2024
%Y A018133 Cf. A011092.
%K A018133 nonn
%O A018133 0,3
%A A018133 _N. J. A. Sloane_