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%I #32 Jun 29 2024 11:17:47
%S 0,5,11,605,209,73205,2299,8857805,6061,218405,278179
%N a(n) is the smallest nonnegative integer k where exactly n ordered pairs of positive integers (x, y) exist such that x^2 + 3*x*y + y^2 = k.
%C a(n) is the smallest nonnegative k such that A374089(k) = n.
%C a(n) is of the form 5*k^2 if and only if n is odd.
%C a(12) = 66671.
%C a(14) = 5285401.
%C a(15) = 26427005.
%C a(16) = 187891.
%C a(18) = 1266749.
%C a(20) = 8067191.
%C a(21) = 3197667605. - _Chai Wah Wu_, Jun 29 2024
%C a(24) = 2066801.
%C a(26) = 36735721.
%C a(27) = 183678605. - _Chai Wah Wu_, Jun 28 2024
%F a(2*n) = A374095(n).
%F a(n) <= 5*11^(n-1) for all n >= 1. - _Jason Yuen_, Jun 29 2024
%Y Cf. A328151, A374090.
%Y Cf. A374089, A374095.
%K nonn,more
%O 0,2
%A _Seiichi Manyama_, Jun 28 2024
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