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 A289172 Irregular triangle read by rows: row n lists terms m of A038566(n) such that A001221(m) = A051265(n), with a(1) = 1. 1
 1, 1, 2, 3, 2, 3, 4, 5, 6, 3, 5, 7, 2, 4, 5, 7, 8, 3, 7, 9, 6, 10, 5, 7, 11, 6, 10, 12, 3, 5, 9, 11, 13, 14, 15, 6, 10, 12, 14, 15, 5, 7, 11, 13, 17, 6, 10, 12, 14, 15, 18, 3, 7, 9, 11, 13, 17, 19, 10, 20, 15, 21, 6, 10, 12, 14, 15, 18, 20, 21, 22, 5, 7, 11 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Consider A051265(n), the largest value of A001221(m) for 1 <= m <= n such that gcd(m, n) = 1 (i.e., m is in the reduced residue system or RRS of n, or m is a totative of n). Row n of this sequence consists of m in RRS(n) such that omega(m) = A051265(n). LINKS Michael De Vlieger, Table of n, a(n) for the first 1000 rows, flattened EXAMPLE Triangle begins:    n    T(n,m)                        A051265(n)    1:   1                                     0    2:   1                                     0    3:   2                                     1    4:   3                                     1    5:   2    3    4                           1    6:   5                                     1    7:   6                                     2    8:   3    5    7                           1    9:   2    4    5    7    8                 1   10:   3    7    9                           1   11:   6   10                                2   12:   5    7   11                           1   13:   6   10   12                           2   14:   3    5    9   11   13                 1   15:  14                                     2   16:  15                                     2   17:   6   10   12   14   15                 2   18:   5    7   11   13   17                 1   19:   6   10   12   14   15   18            2   20:   3    7    9   11   13   17   19       1 MATHEMATICA Table[MaximalBy[#, Last][[All, 1]] &@ Map[{#, PrimeNu@ #} &, Cases[Range[n - 1], k_ /; CoprimeQ[n, k]]] /. {} -> {1}, {n, 30}] // Flatten (* Michael De Vlieger, Aug 11 2017 *) CROSSREFS Cf. A001221, A002110, A038566, A048597, A051250, A051265, A051266, A051267, A051268. Sequence in context: A261323 A134986 A216209 * A215653 A286717 A162751 Adjacent sequences:  A289169 A289170 A289171 * A289173 A289174 A289175 KEYWORD nonn,easy,tabf AUTHOR Michael De Vlieger, Aug 11 2017 STATUS approved

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Last modified October 17 16:34 EDT 2018. Contains 316285 sequences. (Running on oeis4.)