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%I #23 Oct 26 2023 08:42:27
%S 1,4,8,14,22,30,41,54,67,82,99,118,138,160,182,206,234,262,292,322,
%T 353,388,425,462,501,542,583,626,671,718,766,818,870,922,976,1030,
%U 1088,1148,1210,1274,1338,1402,1469,1538,1607,1678,1753,1828,1905,1984,2063
%N Convolution of A002024 with itself.
%H Robert Israel, <a href="/A004797/b004797.txt">Table of n, a(n) for n = 0..10000</a>
%H Raphael Schumacher, <a href="https://www.fq.math.ca/Papers1/55-2/Schumacher12132016.pdf">The self-counting identity</a>, Fib. Quart., 55 (No. 2 2017), 157-167.
%F G.f.: (1/(1 - x)^2)*Product_{k>=1} (1 - x^(2*k))^2/(1 - x^(2*k-1))^2. - _Ilya Gutkovskiy_, May 30 2017
%p a002024:= [seq(i$i,i=1..10)]:
%p g002024:= add(a002024[i]*x^(i-1),i=1..nops(a002024)):
%p g:= expand(g002024^2):
%p seq(coeff(g,x,i),i=0..degree(g002024)); # _Robert Israel_, May 30 2017
%o (PARI) nn(n)=(sqrtint(n*8)+1)\2;
%o a(n) = sum(k=1, n, nn(k)*nn(n-k+1)); \\ _Michel Marcus_, May 30 2017
%Y Cf. A002024.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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