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 A130071 Triangle, A007444(k) in each column interspersed with k zeros. 2
 2, 2, 1, 2, 0, 3, 2, 1, 0, 4, 2, 0, 0, 0, 9, 2, 1, 3, 0, 0, 7, 2, 0, 0, 0, 0, 0, 15, 2, 1, 0, 4, 0, 0, 0, 12, 2, 0, 3, 0, 0, 0, 0, 0, 18, 2, 1, 0, 0, 9, 0, 0, 0, 0, 17 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row sums = the primes. T(n,k) = 0 if k does not divide n. If k divides n, extract A007444(k) which become the nonzero terms of row n, sum = n-th prime. Example: The factors of 6 are (1, 2, 3 and 6) = k's for A007444(k) = (2 + 1 + 3 + 7) = p(6) = 13. A007444 = the Moebius transform of the primes, (2, 1, 3, 4, 9, 7, 15, 12,...), as the right diagonal of A130071. LINKS FORMULA Given the Moebius transform of the primes, A007444: (2, 1, 3, 4, 9, 7, 15,...), the k-th term (k= 1,2,3,...) of this sequence generates the k-th column of A130071, interspersed with (k-1) zeros. EXAMPLE First few rows of the triangle are: 2; 2, 1; 2, 0, 3; 2, 1, 0, 4; 2, 0, 0, 0, 9; 2, 1, 3, 0, 0, 7; 2, 0, 0, 0, 0, 0, 15; 2, 1, 0, 4, 0, 0, 0, 12; 2, 0, 3, 0, 0, 0, 0, 0, 18; 2, 1, 0, 0, 9, 0, 0, 0, 0, 17; ... CROSSREFS Cf. A130070, A007444, A054525, A000040. Sequence in context: A203398 A339275 A225064 * A321373 A305615 A038540 Adjacent sequences:  A130068 A130069 A130070 * A130072 A130073 A130074 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, May 05 2007 STATUS approved

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Last modified January 29 05:09 EST 2022. Contains 350672 sequences. (Running on oeis4.)