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 A027422 Triangle T00, T10, T11, T20, T21, T22, etc. where Tmn = number of distinct products ij with m-n<=i,j<=m. 2
 1, 1, 2, 1, 3, 4, 1, 3, 6, 7, 1, 3, 6, 9, 10, 1, 3, 6, 10, 14, 15, 1, 3, 6, 10, 14, 18, 19, 1, 3, 6, 10, 15, 20, 25, 26, 1, 3, 6, 10, 15, 20, 25, 30, 31, 1, 3, 6, 10, 15, 20, 26, 31, 36, 37, 1, 3, 6, 10, 15, 21, 26, 32, 37, 42, 43, 1, 3, 6, 10, 15, 21, 28, 34, 41, 47, 53, 54, 1, 3, 6 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS R. J. Mathar, Table of n, a(n) for n = 0..1890 EXAMPLE 1 ; 1 2 ; 1 3 4 ; 1 3 6 7 ; 1 3 6 9 10 ; 1 3 6 10 14 15 ; 1 3 6 10 14 18 19 ; 1 3 6 10 15 20 25 26 ; 1 3 6 10 15 20 25 30 31 ; 1 3 6 10 15 20 26 31 36 37 ; 1 3 6 10 15 21 26 32 37 42 43 ; 1 3 6 10 15 21 28 34 41 47 53 54 ; 1 3 6 10 15 21 27 34 40 47 53 59 60 ; MAPLE A027422 := proc(m, n)     local L, i, j ;     L := {};     for i from m-n to m do         for j from i to m do             L := L union {i*j};         end do:     end do:     nops(L); end proc: # R. J. Mathar, May 06 2016 CROSSREFS Cf. A027384, A027421. Sequence in context: A059663 A338367 A186975 * A135086 A210561 A210549 Adjacent sequences:  A027419 A027420 A027421 * A027423 A027424 A027425 KEYWORD tabl,nonn,easy AUTHOR EXTENSIONS More terms from Olivier Gérard, Nov 15 1997 STATUS approved

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Last modified May 14 15:54 EDT 2021. Contains 343884 sequences. (Running on oeis4.)