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.

A287686 Numbers that are sums of three consecutive primes (A034961) and also sums of squares of three consecutive primes (A133529).

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%I A287686 #10 May 30 2017 23:29:15
%S A287686 83,366819,1055019,1947411,2740107,3694179,6627579,8851251,9430899,
%T A287686 20243811,28391619,37545291,38242083,49459179,56550291,88205211,
%U A287686 101931891,103429491,108060339,135085851,176962659,183973851,194907051,196911171,212874531,249687699,271986651
%N A287686 Numbers that are sums of three consecutive primes (A034961) and also sums of squares of three consecutive primes (A133529).
%C A287686 The only prime number is 83.
%H A287686 Chai Wah Wu, <a href="/A287686/b287686.txt">Table of n, a(n) for n = 1..10000</a>
%e A287686 83=A034961(9)=A133529(2),
%e A287686 366819=A034961(11502)=A133529(69),
%e A287686 1055019=A034961(30105)=A133529(107),
%e A287686 1947411=A034961(52758)=A133529(139),
%e A287686 2740107=A034961(72260)=A133529(161),
%e A287686 3694179=A034961(95152)=A133529(185).
%o A287686 (Python)
%o A287686 from __future__ import division
%o A287686 from sympy import prevprime, nextprime, isprime
%o A287686 A287686_list, p2, q2, r2, r = [], 4, 9, 25, 5
%o A287686 while r < 10**6:
%o A287686     n = p2+q2+r2
%o A287686     m = n//3
%o A287686     pm, nm = prevprime(m), nextprime(m)
%o A287686     k = n - pm - nm
%o A287686     if isprime(m):
%o A287686         if m == k:
%o A287686             A287686_list.append(n)
%o A287686     else:
%o A287686         if nextprime(nm) == k or prevprime(pm) == k:
%o A287686             A287686_list.append(n)
%o A287686     s = nextprime(r)
%o A287686     p2, q2, r2, r = q2, r2, s**2, s # _Chai Wah Wu_, May 30 2017
%Y A287686 Cf. A034961 Sums of three consecutive primes. A133529 Sum of squares of three consecutive primes.
%K A287686 nonn
%O A287686 1,1
%A A287686 _Zak Seidov_, May 29 2017