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A200977 Smallest number expressible in the form a^2 + 2b^2, with positive integers a and b, in exactly n ways. 2

%I #26 Oct 30 2018 10:31:02

%S 3,27,99,297,891,1683,8019,5049,18513,15147,649539,31977,314721,

%T 136323,166617,95931,10673289,351747,64304361,287793,1499553,8450649,

%U 127680201,863379,20160657,99379467,5979699,5180274,1235641473,3165723,50984802,3933171

%N Smallest number expressible in the form a^2 + 2b^2, with positive integers a and b, in exactly n ways.

%C Incidentally all terms are multiples of 3.

%e 3 = 1+2*1^2.

%e 27 = 3+2*3^2 = 5^2+2*1^2.

%e 99 = 1+2*7^2 = 7^2+2*5^2 = 9^2+2*3^2.

%Y Cf. A154777 (numbers of the form a^2 + 2b^2 with positive integers a, b).

%K nonn

%O 1,1

%A _Zak Seidov_, Nov 29 2011

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