login
A022823
a(n) = [ (2n+1)/(n-1) ] + [ (2n+2)/(n-2) ] + ... + [ (3n-1)/1 ].
0
5, 11, 19, 26, 35, 44, 54, 62, 74, 83, 96, 103, 117, 128, 140, 150, 162, 175, 189, 198, 213, 222, 240, 249, 263, 277, 291, 300, 318, 329, 345, 356, 371, 386, 400, 411, 427, 440, 460, 468, 486, 497, 515, 528, 542, 557, 576, 587, 603, 616, 636
OFFSET
2,1
PROG
(PARI) a(n) = sum(k=1, n-1, (3*n-k)\k); \\ for n>1. Michel Marcus, Mar 24 2013
CROSSREFS
Sequence in context: A286690 A363637 A190756 * A094693 A183004 A163120
KEYWORD
nonn
STATUS
approved