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A101309 Matrix logarithm of A047999 (Pascal's triangle mod 2). 1
0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Row sums equal A000120 (binary 1's-counting sequence). Antidiagonal sums form A101979.

LINKS

Table of n, a(n) for n=0..104.

FORMULA

T(n, k)=1 when n XOR k = 2^m for integer m>=0, T(n, k)=0 elsewhere.

EXAMPLE

T(n,k)=1 when n XOR k is a power of 2:

T(3,2)=1 since 3 XOR 2 = 2^0, T(4,0)=1 since 4 XOR 0 = 2^2,

T(5,1)=1 since 5 XOR 1 = 2^2, T(6,4)=1 since 6 XOR 4 = 2^2.

Rows begin:

[0],

[1, 0],

[1,0, 0],

[0,1, 1,0],

[1,0,0,0, 0],

[0,1,0,0, 1,0],

[0,0,1,0, 1,0,0],

[0,0,0,1, 0,1,1,0],...

PROG

(PARI) T(n, k)=if(n>k&bitxor(n, k)==2^valuation(bitxor(n, k), 2), 1, 0)

CROSSREFS

Cf. A047999, A101979.

Sequence in context: A289741 A127266 A083923 * A141474 A073424 A135993

Adjacent sequences:  A101306 A101307 A101308 * A101310 A101311 A101312

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna, Dec 23 2004

STATUS

approved

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Last modified January 18 13:44 EST 2020. Contains 331007 sequences. (Running on oeis4.)