The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A225892 Numbers of the form p^2 * (p^2 + 1) where p is in A225856. 1

%I

%S 20,90,650,14762,28730,83810,130682,280370,708122,924482,1875530,

%T 4881890,7893290,12120842,13849562,20155610,25416722,28403570,

%U 38956322,47465210,62750162,88538690,104070602,112561490,141170042,163060130,260160770,294517082,352294130

%N Numbers of the form p^2 * (p^2 + 1) where p is in A225856.

%H Amiram Eldar, <a href="/A225892/b225892.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A071253(A225856(n)). - _Amiram Eldar_, Feb 23 2021

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

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

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

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

%K nonn

%O 1,1

%A _Rafael Parra Machio_, May 20 2013

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 1 03:52 EDT 2021. Contains 346384 sequences. (Running on oeis4.)