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A117173 Column 3 of triangle A117170 of Inverse-Shift-Moebius coefficients and so equals the Inverse-Shift-Moebius transform of [0,0,1,0,...]. 4
0, 0, 1, 0, 0, 1, 1, 1, 2, 1, 2, 2, 2, 2, 4, 2, 3, 4, 4, 3, 6, 4, 6, 6, 4, 6, 10, 6, 6, 9, 9, 8, 11, 8, 12, 12, 9, 12, 16, 11, 12, 16, 15, 15, 18, 16, 18, 19, 17, 17, 24, 19, 20, 26, 24, 25, 27, 23, 26, 28, 21, 30, 39, 29, 30, 35, 32, 33, 38, 36, 38, 41, 36, 39, 48, 42, 41, 50, 44, 48 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,9

LINKS

Table of n, a(n) for n=1..80.

PROG

(PARI) {a(n)=if(n<3, 0, prod(i=0, n, matrix(n, n, r, c, if(r>=c, if((r+i)%(c+i)==0, 1, 0))))[n, 3])}

CROSSREFS

Cf. A117170 (triangle), A117171 (column 1), A117172 (column 2), A117174 (row sums).

Sequence in context: A104659 A077197 A320510 * A241061 A103858 A010554

Adjacent sequences:  A117170 A117171 A117172 * A117174 A117175 A117176

KEYWORD

nonn

AUTHOR

Wouter Meeussen and Paul D. Hanna, Mar 05 2006

STATUS

approved

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Last modified September 26 20:34 EDT 2021. Contains 347672 sequences. (Running on oeis4.)