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A056548
a(n) = Sum_{k>=1} round(n/k) where round(1/2) = 0.
1
0, 1, 4, 7, 11, 15, 19, 23, 29, 32, 37, 43, 47, 52, 58, 62, 68, 73, 79, 84, 90, 94, 100, 108, 112, 117, 124, 128, 136, 142, 146, 152, 160, 165, 171, 177, 183, 188, 196, 202, 208, 215, 219, 227, 233, 237, 247, 253, 259, 263, 272, 277, 283, 293, 297, 303, 311, 315
OFFSET
0,3
FORMULA
a(n) = A056549(n) - A001227(n).
Conjecture: a(n) = Sum_{k=n..2n-1} d(k), where d is the number of divisors function (A000005). - Ridouane Oudra, Apr 29 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Henry Bottomley, Jun 21 2000
STATUS
approved