A056549 a(n) = Sum_{k>=1} round(n/k) where round(1/2)=1.

0, 2, 5, 9, 12, 17, 21, 25, 30, 35, 39, 45, 49, 54, 60, 66, 69, 75, 82, 86, 92, 98, 102, 110, 114, 120, 126, 132, 138, 144, 150, 154, 161, 169, 173, 181, 186, 190, 198, 206, 210, 217, 223, 229, 235, 243, 249, 255, 261, 266, 275, 281, 285, 295, 301, 307, 313, 319

Offset

0,2

Links

Table of n, a(n) for n=0..57.

Formula

a(n) = A056548(n) + A001227(n).

From Ridouane Oudra, Oct 12 2025: (Start)

a(n) = Sum_{k=1..n} tau(n+k), where tau = A000005.

a(n) = Sum_{k=n+1..2*n} tau(k).

a(n) = A062550(n) - A006218(n).

a(n) = A002378(n) - A351355(n).

a(n) = A156745(n) + A075989(n).

a(n) = A077024(n) + A000027(n). (End)

Crossrefs

Cf. A000005, A001227, A006218, A056548, A077024, A062550, A002378, A351355, A156745, A075989,

Sequence in context: A354835 A385327 A086343 * A034806 A226822 A034307

Adjacent sequences: A056546 A056547 A056548 * A056550 A056551 A056552

Keyword

easy,nonn

Author

Henry Bottomley, Jun 21 2000

Status

approved