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%I #2 May 01 2014 02:47:11
%S 4,0,0,0,0,0,8,0,0,8,12,0,8,0,12,0,0,0,0,0,0,0,0,8,16,8,0,0,0,0,0,24,
%T 24,0,0,0,4,0,0,0,28,0,0,0,4,16,0,16,0,0,0,0,16,0,16,16,0,16,0,0,0,0,
%U 0,16,0,16,24,0,0,8,16,0,0,16,8,0,0,24,28,0,8,32,28,0,16,0,28,32,8,0,28
%N Differences between the ordinary multiplication table A004247 and Xmult table A048720, computed for {3..n} * {3..n}.
%p [seq(diff_mult_Xmult_table3(j),j=0..119)]; diff_mult_Xmult_table3 := (n) -> (mult_table3(n) - Xmult_table3(n));
%p mult_table3 := (n) -> floor(evalf(((((trinv(n)-1)*(((1/2)*trinv(n))+1))-n)+3) * (3+(n-((trinv(n)*(trinv(n)-1))/2))) ));
%p Xmult_table3 := (n) -> Xmult( ((((trinv(n)-1)*(((1/2)*trinv(n))+1))-n)+3),(3+(n-((trinv(n)*(trinv(n)-1))/2))) );
%Y Cf. "Zoomed out" variant: A061858, trinv given at A054425. The first, third and fifth diagonals are given by A048728-A048730.
%K nonn,tabl
%O 0,1
%A _Antti Karttunen_, May 11 2001