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 A143620 Triangle read by rows, square of A054521, 1<=k<=n. 2
 1, 1, 0, 2, 0, 0, 2, 1, 0, 0, 4, 1, 1, 0, 0, 2, 1, 1, 1, 0, 0, 6, 2, 2, 1, 1, 0, 0, 4, 3, 2, 2, 1, 1, 0, 0, 6, 2, 4, 2, 2, 1, 1, 0, 0, 4, 3, 1, 2, 2, 1, 1, 1, 0, 0, 10, 4, 5, 3, 4, 1, 3, 1, 1, 0, 0, 4, 3, 3, 3, 2, 2, 1, 1, 1, 1, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Left border = phi(n), A000010. Row sums = A053570: (1, 1, 2, 3, 6, 5, 12, 13,...). LINKS FORMULA Triangle read by rows, square of A054521, 1<=k<=n EXAMPLE First few rows of the triangle = 1; 1, 0; 2, 0, 0; 2, 1, 0, 0; 4, 1, 1, 0, 0; 2, 1, 1, 1, 0, 0; 6, 2, 2, 1, 1, 0, 0; 4, 3, 2, 2, 1, 1, 0, 0; 6, 2, 4, 2, 2, 1, 1, 0, 0; ... CROSSREFS Cf. A054521, A000010, A053570. Sequence in context: A238354 A353836 A161364 * A291529 A236417 A238304 Adjacent sequences: A143617 A143618 A143619 * A143621 A143622 A143623 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Aug 27 2008 STATUS approved

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Last modified February 8 23:03 EST 2023. Contains 360153 sequences. (Running on oeis4.)