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.

A188226 Smallest number having exactly n divisors of the form 8*k + 7.

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%I A188226 #18 Apr 10 2021 08:07:44
%S A188226 1,7,63,315,945,1575,3465,19845,10395,17325,26775,127575,45045,266805,
%T A188226 190575,155925,135135,2480625,225225,130203045,405405,1289925,2168775,
%U A188226 1715175,675675,3898125,3468465,1576575,3239775,67798585575,2027025,16769025,2297295,20539575,42170625,27286875,3828825,117661005
%N A188226 Smallest number having exactly n divisors of the form 8*k + 7.
%C A188226 A188172(a(n)) = n and A188172(m) <> n for m < a(n).
%H A188226 Bert Dobbelaere, <a href="/A188226/b188226.txt">Table of n, a(n) for n = 0..200</a>
%o A188226 (Haskell)
%o A188226 import Data.List  (elemIndex)
%o A188226 import Data.Maybe (fromJust)
%o A188226 a188226 n = a188226_list !! n
%o A188226 a188226_list =
%o A188226    map (succ . fromJust . (`elemIndex` (map a188172 [1..]))) [0..]
%Y A188226 Cf. A004771, A141164, A188172.
%Y A188226 Smallest number having exactly n divisors of the form 8*k + i: A343104 (i=1), A343105 (i=3), A343106 (i=5), this sequence (i=7).
%K A188226 nonn
%O A188226 0,2
%A A188226 _Reinhard Zumkeller_, Mar 26 2011
%E A188226 a(19)-a(35) from _Nathaniel Johnston_, Apr 06 2011
%E A188226 More terms from _Bert Dobbelaere_, Apr 09 2021