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 A304572 Triangle read by rows: T(n,k) = 1 if k does not divide n^e, positive nonzero integers, and gcd(n,k) > 1. 2
 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1 COMMENTS T(n,k) = 1 iff both A304569(n,k) = 0 and A054521(n,k) = 0; T(n,k) = 0 otherwise. This sequence contains 1 where 1 appears in row n of A304571 but not A304569. Row n of A272619 contains indices of 1 in this sequence. A243823(n) = total of row n in this sequence. Rows n for n prime and n <= 6 contain only zeros; all other rows have at least one 1. T(n,k) = 0 for k prime. LINKS Michael De Vlieger, Table of n, a(n) for n = 1..11325 (rows 1 <= n <= 150) Michael De Vlieger, Image of rows 1 <= n <= 2310 EXAMPLE Table begins: 0; 0, 0; 0, 0, 0; 0, 0, 0, 0; 0, 0, 0, 0, 0; 0, 0, 0, 0, 0, 0; 0, 0, 0, 0, 0, 0, 0; 0, 0, 0, 0, 0, 1, 0, 0; 0, 0, 0, 0, 0, 1, 0, 0, 0; 0, 0, 0, 0, 0, 1, 0, 0, 0, 0; 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0; 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0; ... MATHEMATICA Table[Array[Boole[And[PowerMod[n, Floor@ Log2@ n, #] != 0, GCD[n, #] > 1]] &, n], {n, 13}] // Flatten (* Second program: extended data in rows from PNG image above: first, download the PNG and save it as "a304572.png", provides 2669205 terms: *) MapIndexed[Take[#1, First@ #2] &, ImageData@ ColorNegate@ Import["a304572.png", "PNG"]] (* Michael De Vlieger, Jul 02 2018 *) PROG (PARI) T(n, k) = {my(r=vecprod(factor(k)[, 1])); n%r && gcd(n, k)<>1} \\ Andrew Howroyd, Nov 08 2018 CROSSREFS Cf. A054521, A243823, A272619, A304569, A304571. Sequence in context: A072769 A322437 A322438 * A070204 A011745 A011744 Adjacent sequences:  A304569 A304570 A304571 * A304573 A304574 A304575 KEYWORD nonn,easy,tabl AUTHOR Michael De Vlieger, May 23 2018 STATUS approved

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Last modified August 8 05:25 EDT 2020. Contains 336290 sequences. (Running on oeis4.)