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 A277648 Triangle T(n,k) = A277647(n, A005117(k)), read by rows. 8
 1, 2, 1, 1, 3, 2, 1, 1, 1, 1, 4, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 5, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 6, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 4, 4, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 8, 5, 4, 3, 3, 3, 2, 2, 2, 2, 2, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The columns of this triangle are the columns of A277647 with squarefree index. Other that the first (with length 1), row n has length A278100(n). LINKS FORMULA T(n,k) = A000196(A277646(n,A005117(k))). T(n,k) sqrt(A005117(k)) <= n < (T(n,k)+1) sqrt(A005117(k)). EXAMPLE Triangle begins: 1; 2, 1, 1; 3, 2, 1, 1, 1, 1; 4, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1; ... where the first 11 terms of A005117(k) are 1, 2, 3, 5, 6, 7,10,11,13,14,15. MATHEMATICA DeleteCases[#, 0] & /@ Table[Boole[SquareFreeQ@ k] Floor[n/Sqrt@ k], {n, 8}, {k, n^2}] (* Michael De Vlieger, Nov 24 2016 *) PROG (Magma) A277647:=func; A277648_row:=func; &cat[A277648_row(n):n in[1..8]]; (PARI) row(n)={apply(k->sqrtint(n^2\k), select(issquarefree, [1..n^2]))} for(n=1, 6, print(row(n))) \\ Andrew Howroyd, Feb 28 2018 CROSSREFS Cf. A277646, A277647. Sequence in context: A145975 A211028 A239001 * A026792 A334301 A139100 Adjacent sequences:  A277645 A277646 A277647 * A277649 A277650 A277651 KEYWORD nonn,tabf,easy AUTHOR Jason Kimberley, Nov 10 2016 EXTENSIONS Missing a(3009) in b-file inserted by Andrew Howroyd, Feb 28 2018 STATUS approved

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Last modified June 17 05:53 EDT 2021. Contains 345080 sequences. (Running on oeis4.)