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A090173 Triangle read by rows, related to Pascal's triangle read mod 2. 1
0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,1

REFERENCES

Y. Moshe, The density of 0's in recurrence double sequences, J Number Theory, 103 (2003), 109-121; see Fig. 2.

FORMULA

T(n, k) = T(n-1, k) + T(n-1, k-1) + T(n-2, k) + T(n-2, k-1) + T(n-2, j-2) for n >= 2, k >= 0, with initial conditions specified by first two rows.

EXAMPLE

0; 0,1; 0,1,1; 0,0,1,0; 0,1,1,1,1; ...

CROSSREFS

Cf. A007318, A083093, A090171-A090174.

a(n, k) = A090174(n-1, k-1), k>0, 0 otherwise.

Sequence in context: A095907 A056051 A143541 * A072784 A092436 A164056

Adjacent sequences:  A090170 A090171 A090172 * A090174 A090175 A090176

KEYWORD

nonn,easy,tabl

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Jan 19 2004

EXTENSIONS

Edited and extended by Christian G. Bower (bowerc(AT)usa.net), Jan 20 2004

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Last modified February 15 19:02 EST 2012. Contains 205852 sequences.