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A218446 a(n) = Sum_{k>=0} floor(n/(5*k + 3)). 2
0, 0, 0, 1, 1, 1, 2, 2, 3, 4, 4, 4, 5, 6, 6, 7, 8, 8, 10, 10, 10, 11, 11, 12, 14, 14, 15, 16, 17, 17, 18, 18, 19, 21, 21, 21, 23, 23, 24, 26, 27, 27, 28, 29, 29, 30, 31, 31, 34, 34, 34, 35, 36, 37, 39, 39, 41, 42, 43, 43, 44, 44, 44, 46, 47, 48, 50, 50, 51, 53, 53, 53, 56, 57, 57, 58, 59, 59, 62, 62, 63 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

COMMENTS

Partial sums of A001878.

LINKS

Table of n, a(n) for n=0..80.

MATHEMATICA

Accumulate[Table[Count[Divisors[n], _?(Mod[#, 5]==3&)], {n, 0, 90}]] (* Harvey P. Dale, Nov 08 2012 *)

PROG

(PARI) a(n)=sum(k=0, n, (n\(5*k+3)))

(Maxima) A218446[n]:=sum(floor(n/(5*k+3)), k, 0, n)$

makelist(A218446[n], n, 0, 80); /* Martin Ettl, Oct 29 2012 */

CROSSREFS

Sequence in context: A046699 A239105 A302255 * A102548 A004001 A086841

Adjacent sequences:  A218443 A218444 A218445 * A218447 A218448 A218449

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Oct 28 2012

STATUS

approved

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Last modified June 19 13:11 EDT 2019. Contains 324222 sequences. (Running on oeis4.)