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A103447 Triangle read by rows: T(n,k) is mobius(binom(n,k)) (0<=k<=n). 3
1, 1, 1, 1, -1, 1, 1, -1, -1, 1, 1, 0, 1, 0, 1, 1, -1, 1, 1, -1, 1, 1, 1, 1, 0, 1, 1, 1, 1, -1, 1, 1, 1, 1, -1, 1, 1, 0, 0, 0, -1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, -1, 1, -1, 1, 1, 1, 1, -1, 1, -1, 1, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, -1, 0, 1, 1, -1, -1, -1, -1, 0, 0, 0, 0, -1, -1, -1, -1, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Row n contains n+1 terms. Row sums yield A103448 T(2n,n)=0 for all n except n=0,1,2 and 4 (Granville and Ramare).

REFERENCES

A. Granville and O. Ramare, Explicit bounds on exponential sums and the scarcity of squarefree binomial coefficients, Mathematika 43, 73-107, 1996.

FORMULA

T(n, k)=mobius(binom(n, k)) (0<=k<=n).

EXAMPLE

T(3,2)=-1 because binom(3,2)=3 and mobius(3)=-1.

Triangle begins:

.1;

.1,1;

.1,-1,1;

.1,-1,-1,1;

.1,0,1,0,1;

.1,-1,1,1,-1,1;

MAPLE

with(numtheory):T:=proc(n, k) if k<=n then mobius(binomial(n, k)) else 0 fi end: for n from 0 to 13 do seq(T(n, k), k=0..n) od; # yields sequence in triangular form

CROSSREFS

Cf. A103448, A103449.

Sequence in context: A014383 A014152 A014295 * A089829 A178788 A131217

Adjacent sequences:  A103444 A103445 A103446 * A103448 A103449 A103450

KEYWORD

sign,tabl

AUTHOR

Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 06 2005

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Last modified February 14 11:14 EST 2012. Contains 205619 sequences.