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 A068344 Square array read by antidiagonals of T(n,k) = sign(n-k). 0
 0, -1, 1, -1, 0, 1, -1, -1, 1, 1, -1, -1, 0, 1, 1, -1, -1, -1, 1, 1, 1, -1, -1, -1, 0, 1, 1, 1, -1, -1, -1, -1, 1, 1, 1, 1, -1, -1, -1, -1, 0, 1, 1, 1, 1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, 0, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, 0, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, 1, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS FORMULA a(n) = sign(A002260(n) - A004736(n)) or a(n) = sign((n-t(t+1)/2) - (t*t+3*t+4)/2-n)) where t = floor((-1+sqrt(8*n-7))/2).  - Boris Putievskiy, Dec 24 2012 EXAMPLE The start of the array is: 0; -1,...1; -1,...0,...1; -1,..-1,...1,...1; -1,..-1,...0,...1,...1; . . . - Boris Putievskiy, Dec 24 2012 CROSSREFS Cf. A049581, A057427, A057428, A002260, A004736. As a straight sequence, a(n)=0 when n is in A046092. A023532 seen as a triangle is half this square. Sequence in context: A285596 A257680 A323377 * A161382 A138886 A269528 Adjacent sequences:  A068341 A068342 A068343 * A068345 A068346 A068347 KEYWORD easy,sign,tabl AUTHOR Henry Bottomley, Mar 06 2002 STATUS approved

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Last modified December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)