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%I #43 Oct 04 2021 13:52:55
%S 15,32,96,960,5280,640320
%N Rounded near-integers (exp(Pi*sqrt(h)) - 744)^(1/3) where h is A003173(n+3) (Heegner numbers of the form 4p-1 where p is prime).
%F a(n) = (-j((1 + i*sqrt(h(n))) / 2))^(1/3) where h(n) = A003173(n+3) and j(x) is the j-invariant. - _Andrey Zabolotskiy_, Sep 30 2021
%e a(1) = 15 because 15^3 + 744 ~ exp(Pi*sqrt(7)).
%e a(2) = 32 because 32^3 + 744 ~ exp(Pi*sqrt(11)).
%e a(3) = 96 because 96^3 + 744 ~ exp(Pi*sqrt(19)).
%e a(4) = 960 because 960^3 + 744 ~ exp(Pi*sqrt(43)).
%e a(5) = 5280 because 5280^3 + 744 ~ exp(Pi*sqrt(67)).
%e a(6) = 640320 because 640320^3 + 744 ~ exp(Pi*sqrt(163)).
%Y Cf. A003173, A305500.
%Y A267195 is a supersequence (negated).
%K nonn,fini,full
%O 1,1
%A _Artur Jasinski_, Nov 09 2011
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