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Table of coefficients of Product_{k=1..n} (1+x^A000120(k)).
1

%I #16 Jul 22 2023 17:36:26

%S 1,1,1,1,2,1,1,2,2,2,1,1,3,4,4,3,1,1,3,5,7,7,5,3,1,1,3,6,10,12,12,10,

%T 6,3,1,1,3,6,11,15,18,20,18,15,11,6,3,1,1,4,9,17,26,33,38,38,33,26,17,

%U 9,4,1,1,4,10,21,35,50,64,71,71,64,50,35,21,10,4,1,1,4,11,25,45,71,99,121,135,135,121,99,71,45,25,11,4,1

%N Table of coefficients of Product_{k=1..n} (1+x^A000120(k)).

%C Also table of coefficients of Product_{k=0..n} (1+x^A000120(k))/2.

%C Row sums are 2^n.

%C Row n has 1+A000788(n) elements.

%H Amiram Eldar, <a href="/A102418/b102418.txt">Table of n, a(n) for n = 0..14638</a> (row 0..100)

%e Table begins:

%e 1;

%e 1, 1;

%e 1, 2, 1;

%e 1, 2, 2, 2, 1;

%e 1, 3, 4, 4, 3, 1;

%e 1, 3, 5, 7, 7, 5, 3, 1;

%e ...

%t row[n_] := CoefficientList[Product[1 + x^DigitCount[k, 2, 1], {k, 1, n}], x]; Table[row[n], {n, 0, 10}] // Flatten (* _Amiram Eldar_, Jul 22 2023 *)

%Y Cf. A000120, A000788.

%K nonn,tabf

%O 0,5

%A _Paul Barry_, Jan 08 2005