A061859 Differences between the ordinary multiplication table A004247 and Xmult table A048720, computed for {3..n} * {3..n}.

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, 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, 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

Offset

0,1

Links

Table of n, a(n) for n=0..90.

Maple

[seq(diff_mult_Xmult_table3(j), j=0..119)]; diff_mult_Xmult_table3 := (n) -> (mult_table3(n) - Xmult_table3(n));
mult_table3 := (n) -> floor(evalf(((((trinv(n)-1)*(((1/2)*trinv(n))+1))-n)+3) * (3+(n-((trinv(n)*(trinv(n)-1))/2))) ));
Xmult_table3 := (n) -> Xmult( ((((trinv(n)-1)*(((1/2)*trinv(n))+1))-n)+3), (3+(n-((trinv(n)*(trinv(n)-1))/2))) );

Crossrefs

Cf. "Zoomed out" variant: A061858, trinv given at A054425. The first, third and fifth diagonals are given by A048728-A048730.

Sequence in context: A089371 A318679 A133886 * A348250 A289110 A287287

Adjacent sequences: A061856 A061857 A061858 * A061860 A061861 A061862

Keyword

nonn,tabl

Author

_Antti Karttunen_, May 11 2001

Status

approved