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A368041 a(n) is the least number k such that k^2 can be written as the difference of two positive squares in exactly n ways.

%I A368041 #25 Nov 08 2024 07:20:17
%S A368041 1,3,8,16,12,64,128,24,512,1024,48,4096,72,60,32768,65536,192,144,
%T A368041 524288,384,2097152,4194304,120,16777216,432,1536,134217728,576,3072,
%U A368041 1073741824,2147483648,240,1152,17179869184,12288,68719476736,137438953472,360,1728,1099511627776
%N A368041 a(n) is the least number k such that k^2 can be written as the difference of two positive squares in exactly n ways.
%C A368041 Index of first occurrence of n in A046079.
%C A368041 All the terms are of the form 2^m * A147516(k), m >= 0, k >= 1. - _Amiram Eldar_, Nov 08 2024
%H A368041 Amiram Eldar, <a href="/A368041/b368041.txt">Table of n, a(n) for n = 0..999</a>
%F A368041 a(n) = min(A122842(n+1), 2*A071571(n)). - _Jon E. Schoenfield_, Dec 09 2023
%e A368041 a(2) = 8: 8^2 = 10^2 - 6^2 = 17^2 - 15^2.
%Y A368041 Cf. A025487, A046079, A068314, A071571, A094191, A100073, A122842, A147516.
%K A368041 nonn
%O A368041 0,2
%A A368041 _Ilya Gutkovskiy_, Dec 09 2023
%E A368041 a(26)-a(29) from _Michel Marcus_, Dec 09 2023
%E A368041 a(30)-a(39) from _Jon E. Schoenfield_, Dec 09 2023