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A117947 T(n,k)=L(C(n,k)/3) where L(j/p) is the Legendre symbol of j and p. 5
1, 1, 1, 1, -1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, -1, 1, 1, -1, 1, 1, 0, 0, -1, 0, 0, 1, 1, 1, 0, -1, -1, 0, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, -1, 1, 0, 0, 0, 0, 0, 0, 1, -1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, -1, 1, 1, -1, 1, 0, 0, 0, 1, -1, 1, 1, -1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Row sums are A059126. Diagonal sums are A117963. Could be called the Legendre-binomial matrix for p=3.

The matrix square equals triangle A117939; the matrix log equals triangle A120854 divided by 2. - Paul D. Hanna, Jul 08 2006

LINKS

Table of n, a(n) for n=0..119.

FORMULA

Triangle begins 1, 1, 1, 1, -1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, -1, 1, 1, -1, 1, 1, 0, 0, -1, 0, 0, 1, 1, 1, 0, -1, -1, 0, 1, 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, -1, 1, 0, 0, 0, 0, 0, 0, 1, -1, 1

T(n,k) = balanced ternary digit of C(n,k) mod 3. - Paul D. Hanna, Jul 08 2006

PROG

(PARI) T(n, k)=(binomial(n, k)+1)%3-1 - Paul D. Hanna, Jul 08 2006

CROSSREFS

Cf. A117939 (matrix square), A120854 (2*log).

Sequence in context: A185917 A143104 A127236 * A175860 A092152 A179775

Adjacent sequences:  A117944 A117945 A117946 * A117948 A117949 A117950

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Apr 05 2006

STATUS

approved

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Last modified April 10 18:17 EDT 2021. Contains 342853 sequences. (Running on oeis4.)