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A105586
A Moebius-binomial triangle.
4
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
0,1
COMMENTS
n-th row is all 1's unless n is not squarefree (see A013929). Row sums are A105587. Diagonal sums are A105588. Inverse is A105589.
FORMULA
Number triangle T(n, k)=if(k<=n, binomial(abs(mu(n)), abs(mu(k))), 0)
EXAMPLE
Triangle starts
1;
1,1;
1,1,1;
1,1,1,1;
0,0,0,0,1;
1,1,1,1,1,1;
1,1,1,1,1,1,1;
1,1,1,1,1,1,1,1;
0,0,0,0,1,0,0,0,1;
CROSSREFS
Sequence in context: A336546 A209929 A336556 * A202022 A136522 A352871
KEYWORD
easy,nonn,tabl
AUTHOR
Paul Barry, Apr 14 2005
STATUS
approved