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 A155031 Triangle T(n, k) = 0 if n==0 (mod k) otherwise -1 with T(n, n) = 1 and T(n, 0) = 0, read by rows. 3
 1, 0, 1, 0, -1, 1, 0, 0, -1, 1, 0, -1, -1, -1, 1, 0, 0, 0, -1, -1, 1, 0, -1, -1, -1, -1, -1, 1, 0, 0, -1, 0, -1, -1, -1, 1, 0, -1, 0, -1, -1, -1, -1, -1, 1, 0, 0, -1, -1, 0, -1, -1, -1, -1, 1, 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1, 0, 0, 0, 0, -1, 0, -1, -1, -1, -1, -1, 1, 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS G. C. Greubel, Rows n = 1..30 of the triangle, flattened FORMULA T(n, k) = A154990(n, k) * A155029(n, k). T(n, k) = 0 if n==0 (mod k) otherwise -1 with T(n, n) = 1 and T(n, 0) = 0. EXAMPLE Table begins:   1;   0,  1;   0, -1,  1;   0,  0, -1,  1;   0, -1, -1, -1,  1;   0,  0,  0, -1, -1,  1;   0, -1, -1, -1, -1, -1,  1;   0,  0, -1,  0, -1, -1, -1,  1;   0, -1,  0, -1, -1, -1, -1, -1, 1; MATHEMATICA T[n_, k_]:= If[k==n, 1, If[k==1 || Mod[n, k]==0, 0, -1]]; Table[T[n, k], {n, 12}, {k, n}] //Flatten (* G. C. Greubel, Mar 08 2021 *) PROG (Sage) flatten([[1 if k==n else 0 if (k==1 or n%k==0) else -1 for k in [1..n]] for n in [1..12]]) # G. C. Greubel, Mar 08 2021 (Magma) [k eq n select 1 else (k eq 1 or n mod k eq 0) select 0 else -1: k in [1..n], n in [1..12]]; // G. C. Greubel, Mar 08 2021 CROSSREFS Cf. A154990, A155029. Sequence in context: A187034 A101688 A155029 * A134540 A318962 A128430 Adjacent sequences:  A155028 A155029 A155030 * A155032 A155033 A155034 KEYWORD sign,tabl AUTHOR Mats Granvik, Jan 19 2009 STATUS approved

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Last modified May 7 01:08 EDT 2021. Contains 343632 sequences. (Running on oeis4.)