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A167807

Square pyramidal numbers which are sums of three consecutive primes.

1015, 25585, 1623245, 2127685, 7838831, 8865649, 19849115, 52051769, 73998155, 88409285, 91753025, 161553785, 216862421, 289872105, 347016319, 382029011, 466430159, 835713879, 1077314939, 1223359835, 1509659555, 1584781241

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OFFSET

1,1

COMMENTS

Intersection of A000330 (Square pyramidal numbers) and A034961 (Sums of three consecutive primes).

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

EXAMPLE

1015=A034961(67)=A000330(14)

25585=A034961(1062)=A000330(42).

PROG

(Python)

from __future__ import division

from sympy import nextprime, prevprime

A167807_list = []

for i in range(3, 10**6):

n = i*(i+1)*(2*i+1)//6

p2 = prevprime(n//3)

p1, p3 = prevprime(p2), nextprime(p2)

q = p1+p2+p3

while q <= n:

if q == n:

A167807_list.append(n)

p1, p2, p3 = p2, p3, nextprime(p3)

q = p1+p2+p3 # Chai Wah Wu, Dec 31 2015

CROSSREFS

Cf. A000330, A034961.

Sequence in context: A225717 A117807 A223089 * A118879 A023083 A221808

Adjacent sequences: A167804 A167805 A167806 * A167808 A167809 A167810

KEYWORD

nonn

AUTHOR

Zak Seidov, Nov 12 2009

EXTENSIONS

a(6)-a(22) from Donovan Johnson, Nov 15 2009

STATUS

approved

URL: https://oeis.org/A167807

⇱ A167807 - OEIS