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A225892 Numbers of the form p^2 * (p^2 + 1) where p is in A225856. 1
20, 90, 650, 14762, 28730, 83810, 130682, 280370, 708122, 924482, 1875530, 4881890, 7893290, 12120842, 13849562, 20155610, 25416722, 28403570, 38956322, 47465210, 62750162, 88538690, 104070602, 112561490, 141170042, 163060130, 260160770, 294517082, 352294130 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A071253(A225856(n)). - Amiram Eldar, Feb 23 2021

EXAMPLE

a(2) = 3^2(3^2+1) = 3^4+3^2 = 90.

a(5) = 13^2(13^2+1) = 13^4+13^2 = 28730.

MATHEMATICA

p = Select[Prime[Range[60]], SquareFreeQ[#^2+1]&]; p^2 * (p^2+1)

CROSSREFS

Cf. A071253, A225856 (primes p such that p^2+1 is squarefree).

Sequence in context: A344334 A225882 A281768 * A211140 A200431 A172200

Adjacent sequences:  A225889 A225890 A225891 * A225893 A225894 A225895

KEYWORD

nonn

AUTHOR

Rafael Parra Machio, May 20 2013

STATUS

approved

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Last modified June 14 09:06 EDT 2021. Contains 345018 sequences. (Running on oeis4.)