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A167807 Square pyramidal numbers which are sums of three consecutive primes.

%I A167807 #7 Dec 31 2015 11:32:19
%S A167807 1015,25585,1623245,2127685,7838831,8865649,19849115,52051769,
%T A167807 73998155,88409285,91753025,161553785,216862421,289872105,347016319,
%U A167807 382029011,466430159,835713879,1077314939,1223359835,1509659555,1584781241
%N A167807 Square pyramidal numbers which are sums of three consecutive primes.
%C A167807 Intersection of A000330 (Square pyramidal numbers) and A034961 (Sums of three consecutive primes).
%H A167807 Chai Wah Wu, <a href="/A167807/b167807.txt">Table of n, a(n) for n = 1..10000</a>
%e A167807 1015=A034961(67)=A000330(14)
%e A167807 25585=A034961(1062)=A000330(42).
%o A167807 (Python)
%o A167807 from __future__ import division
%o A167807 from sympy import nextprime, prevprime
%o A167807 A167807_list = []
%o A167807 for i in range(3,10**6):
%o A167807     n = i*(i+1)*(2*i+1)//6
%o A167807     p2 = prevprime(n//3)
%o A167807     p1, p3 = prevprime(p2), nextprime(p2)
%o A167807     q = p1+p2+p3
%o A167807     while q <= n:
%o A167807         if q == n:
%o A167807             A167807_list.append(n)
%o A167807         p1, p2, p3 = p2, p3, nextprime(p3)
%o A167807         q = p1+p2+p3 # _Chai Wah Wu_, Dec 31 2015
%Y A167807 Cf. A000330, A034961.
%K A167807 nonn
%O A167807 1,1
%A A167807 _Zak Seidov_, Nov 12 2009
%E A167807 a(6)-a(22) from _Donovan Johnson_, Nov 15 2009