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 A224531 Triangle in which row n > 1 has the n values x such that phi(x) = A007374(n), We define the first row to be 0. 3
 0, 1, 2, 3, 4, 6, 5, 8, 10, 12, 15, 16, 20, 24, 30, 13, 21, 26, 28, 36, 42, 51, 64, 68, 80, 96, 102, 120, 37, 57, 63, 74, 76, 108, 114, 126, 41, 55, 75, 82, 88, 100, 110, 132, 150, 35, 39, 45, 52, 56, 70, 72, 78, 84, 90, 65, 104, 105, 112, 130, 140, 144, 156, 168, 180, 210 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS T. D. Noe, Rows n = 1..100 of triangle, flattened D. Bressoud, CNT.m Computational Number Theory Mathematica package. EXAMPLE Triangle: 0, 1, 2, 3, 4, 6, 5, 8, 10, 12, 15, 16, 20, 24, 30, 13, 21, 26, 28, 36, 42, 51, 64, 68, 80, 96, 102, 120, 37, 57, 63, 74, 76, 108, 114, 126, 41, 55, 75, 82, 88, 100, 110, 132, 150 MATHEMATICA Needs["CNT`"]; nn = 10; t = Table[{}, {nn}]; n = 0; t[[1]] = {0}; left = nn - 1; While[left > 0, n++; p = PhiInverse[n]; cnt = Length[p]; If[cnt <= nn && t[[cnt]] == {}, t[[cnt]] = p; left--]]; t CROSSREFS Cf. A066420, A224532 (numbers in the first column and diagonal). Sequence in context: A197756 A080738 A032447 * A058213 A080997 A151942 Adjacent sequences:  A224528 A224529 A224530 * A224532 A224533 A224534 KEYWORD nonn,tabl AUTHOR T. D. Noe, Apr 11 2013 STATUS approved

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Last modified September 29 16:13 EDT 2020. Contains 337432 sequences. (Running on oeis4.)