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 A128179 A097807 * A002260. 4
 1, 0, 2, 1, 0, 3, 0, 2, 0, 4, 1, 0, 3, 0, 5, 0, 2, 0, 4, 0, 6, 1, 0, 3, 0, 5, 0, 7, 0, 2, 0, 4, 0, 6, 0, 8, 1, 0, 3, 0, 5, 0, 7, 0, 9, 0, 2, 0, 4, 0, 6, 0, 8, 0, 10 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Row sums = A002620: (1, 2, 4, 6, 9, 12, 16, 20, 25, 30,...) General case see A211161. Let B and C be sequences. By b(n) and c(n) denote elements B and C respectively. Table T(n,k) = b(n), if k is odd, c(k) if k is even read by antidiagonals. For this sequence b(n)=n, b(n)=A000027(n), c(n)=0, c(n)=A000004(n). - Boris Putievskiy, Feb 05 2013 LINKS Boris Putievskiy, Transformations [of] Integer Sequences And Pairing Functions arXiv:1212.2732 [math.CO] FORMULA A097807 * A002260 as infinite lower triangular matrices. k-th column = (k, 0, k, 0, ...). T(n,k) = (1-(-1)^k)*n/2; a(n) = (1-(-1)^A004736(n))*A002260(n)/2; a(n) = (1-(-1)^j)*i/2, where i = n-t*(t+1)/2, j = (t*t+3*t+4)/2-n, t = floor((-1+sqrt(8*n-7))/2). - Boris Putievskiy, Feb 05 2013 EXAMPLE From Boris Putievskiy, Feb 05 2013: (Start) The start of the sequence as table 1..0..1..0..1..0..1... 2..0..2..0..2..0..2... 3..0..3..0..3..0..3... 4..0..4..0..4..0..4... 5..0..5..0..5..0..5... 6..0..6..0..6..0..6... 7..0..7..0..7..0..7... . . .(End) First few rows of the triangle are: 1; 0, 2; 1, 0, 3; 0, 2, 0, 4; 1, 0, 3, 0, 5; 0, 2, 0, 4, 0, 6; 1, 0, 3, 0, 5, 0, 7; ... CROSSREFS Cf. A000004, A000027, A002260, A002620, A004736, A097807, A211161. Sequence in context: A014405 A143153 A127448 * A178780 A058558 A210869 Adjacent sequences:  A128176 A128177 A128178 * A128180 A128181 A128182 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Feb 17 2007 STATUS approved

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Last modified January 16 14:39 EST 2022. Contains 350376 sequences. (Running on oeis4.)