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.

A236382 Values of y corresponding to the smallest value of x such that x^2 + y^2 = P, where P is the product of the first n primes of the form 4k + 1, and 0 < x < y.

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%I A236382 #9 May 05 2025 23:01:54
%S A236382 2,8,33,179,1087,6972,50741,396437,3387169,31954512,314715456,
%T A236382 3162851149,33021136387,351019495376,4108577867504,50151584231673,
%U A236382 628397549315889,8265279309778838,111197960474124352,1544811437679174169,21682461771278746182,328115185564476599824
%N A236382 Values of y corresponding to the smallest value of x such that x^2 + y^2 = P, where P is the product of the first n primes of the form 4k + 1, and 0 < x < y.
%e A236382 a(3) = 33 because the solutions to x^2 + y^2 = 5*13*17 are (x,y) = (23,24), (9,32), (4,33), (12,31) and the value of y corresponding to the smallest value of x is 33.
%o A236382 (PARI) a(n) = my(t=1, v); forprimestep(p=5, oo, 4, t*=p; if(!n--, break)); v=qfbsolve(Qfb(1, 0, 1), t, 3); vecmax(vector(#v, i, vecmax(abs(v[i])))); \\ _Jinyuan Wang_, Apr 30 2025
%Y A236382 Cf. A002144, A006278, A236381.
%K A236382 nonn
%O A236382 1,1
%A A236382 _Colin Barker_, Jan 24 2014
%E A236382 a(22) from _Jinyuan Wang_, Apr 30 2025