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A049794 a(n) = T(n,n-2), array T as in A049790. 7
1, 2, 3, 6, 11, 16, 25, 31, 44, 53, 66, 79, 97, 108, 130, 148, 168, 187, 214, 233, 265, 286, 315, 344, 381, 402, 442, 474, 511, 545, 590, 619, 670, 705, 751, 797, 848, 880, 940, 988, 1041, 1087, 1150, 1192, 1263, 1311, 1370, 1431 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 3..1000

MAPLE

seq( `if`(n<5, n-2, add(floor((n-2)/floor((n-4)/j)), j=1..n-4)), n=3..60); # G. C. Greubel, Dec 10 2019

MATHEMATICA

Table[If[n<5, n-2, Sum[Floor[(n-2)/Floor[(n-4)/j]], {j, n-4}]], {n, 3, 60}] (* G. C. Greubel, Dec 10 2019 *)

PROG

(PARI) a(n) = if(n<5, n-2, sum(j=1, n-4, (n-2)\((n-4)\j)) );

vector(60, n, a(n+2) ) \\ G. C. Greubel, Dec 10 2019

(MAGMA) [n lt 5 select n-2 else (&+[Floor((n-2)/Floor((n-4)/j)): j in [1..n-4]]): n in [3..60]]; // G. C. Greubel, Dec 10 2019

(Sage)

def a(n):

    if (n<5): return n-2

    else: return sum(floor((n-2)/floor((n-4)/j)) for j in (1..n-4))

[a(n) for n in (3..60)] # G. C. Greubel, Dec 10 2019

(GAP)

a:= function(n)

    if n<5 then return n-2;

    else return Sum([1..n-4], j-> Int((n-2)/Int((n-4)/j)) );

    fi; end;

List([3..60], n-> a(n) ); # G. C. Greubel, Dec 10 2019

CROSSREFS

Cf. A049790, A049791, A049792, A049793, A049795, A049796.

Sequence in context: A210458 A228864 A289434 * A034031 A121617 A157656

Adjacent sequences:  A049791 A049792 A049793 * A049795 A049796 A049797

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified July 5 21:00 EDT 2020. Contains 335473 sequences. (Running on oeis4.)