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A341712 a(n) = A120963(2*n)/2.

%I A341712 #19 May 12 2022 14:04:09
%S A341712 3,12,39,112,292,710,1629,3567,7505,15266,30140,57983,108981,200625,
%T A341712 362433,643653,1125269,1939149,3297411,5538254,9195371,15104245,
%U A341712 24561098,39562657,63160404,99987453,157029090,244754385,378754786,582124254,888874067,1348842728
%N A341712 a(n) = A120963(2*n)/2.
%C A341712 A bisection of A341710.
%p A341712 with(numtheory):
%p A341712 b:= proc(n) option remember; nops(invphi(n)) end:
%p A341712 g:= proc(n) option remember; `if`(n=0, 1, add(
%p A341712       g(n-j)*add(d*b(d), d=divisors(j)), j=1..n)/n)
%p A341712     end:
%p A341712 a:= n-> g(2*n)/2:
%p A341712 seq(a(n), n=1..40);  # _Alois P. Heinz_, Feb 19 2021
%t A341712 terms = 64; (* number of terms of A120963 *)
%t A341712 nmax = Floor[terms/2];
%t A341712 S[m_] := S[m] = CoefficientList[Product[1/(1 - x^EulerPhi[k]),
%t A341712      {k, 1, m*terms}] + O[x]^(terms+1), x];
%t A341712 S[m = 1];
%t A341712 S[m++];
%t A341712 While[S[m] != S[m-1], m++];
%t A341712 A120963 = S[m];
%t A341712 a[n_ /; 1 <= n <= nmax] := A120963[[2n+1]]/2;
%t A341712 Table[a[n], {n, 1, nmax}] (* _Jean-François Alcover_, May 12 2022 *)
%Y A341712 Cf. A120963, A341710, A341711.
%K A341712 nonn
%O A341712 1,1
%A A341712 _N. J. A. Sloane_, Feb 19 2021