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A183871
a(n) = n + ceiling( (1/5)*n^2 ). Complement of A183870.
1
2, 3, 5, 8, 10, 14, 17, 21, 26, 30, 36, 41, 47, 54, 60, 68, 75, 83, 92, 100, 110, 119, 129, 140, 150, 162, 173, 185, 198, 210, 224, 237, 251, 266, 280, 296, 311, 327, 344, 360, 378, 395, 413, 432, 450, 470, 489, 509, 530, 550, 572, 593, 615, 638, 660, 684, 707, 731, 756, 780, 806, 831, 857, 884, 910, 938, 965, 993, 1022, 1050, 1080, 1109, 1139, 1170, 1200, 1232, 1263, 1295, 1328, 1360
OFFSET
1,1
FORMULA
a(n) = floor( (n+1)*(n+4)/5 ). [Bruno Berselli, Mar 05 2014]
MATHEMATICA
a=5; b=-5;
Table[n+Floor[(a*n+b)^(1/2)], {n, 100}]
Table[n-1+Ceiling[(n*n-b)/a], {n, 80}]
CROSSREFS
Cf. A183870.
Sequence in context: A094568 A251607 A219276 * A211542 A368052 A022955
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jan 07 2011
STATUS
approved