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.

A291466 First of the smallest n consecutive sphenic numbers A007304.

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%I A291466 #6 Oct 18 2017 04:44:40
%S A291466 30,230,1309
%N A291466 First of the smallest n consecutive sphenic numbers A007304.
%C A291466 Every 4th consecutive number is divisible by 4 = 2*2 and therefore is not sphenic, so a(n) does not exist for n >= 4.
%H A291466 Wikipedia, <a href="https://en.wikipedia.org/wiki/Sphenic_number">Sphenic number</a>
%e A291466 30 = 2*3*5 is the first spheric number, so a(1) = 30.
%e A291466 The first case of two consecutive sphenic numbers is 230 = 2*5*23 and 231 = 3*7*11, so a(2) = 230.
%e A291466 The first case of three is 1309 = 7*11*17, 1310 = 2*5*131, and 1311 = 3*19*23, so a(3) = 1309.
%Y A291466 Cf. A007304.
%K A291466 nonn,fini,full
%O A291466 1,1
%A A291466 _Jonathan Sondow_, Oct 17 2017