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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: A276237 A059663 A186975 * A135086 A210561 A210549

Adjacent sequences:  A027419 A027420 A027421 * A027423 A027424 A027425

KEYWORD

tabl,nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Olivier Gérard, Nov 15 1997

STATUS

approved

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Last modified September 26 01:25 EDT 2020. Contains 337346 sequences. (Running on oeis4.)