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A086814
a(n) = ceiling( (1 + n + 2*n^2 + 4*n^3)/(1 + 2*n + n^2) ).
3
2, 5, 9, 12, 16, 20, 24, 27, 31, 35, 39, 43, 47, 51, 55, 59, 63, 67, 71, 75, 79, 83, 87, 91, 95, 99, 103, 107, 111, 115, 119, 123, 127, 131, 135, 139, 143, 147, 151, 155, 159, 163, 167, 171, 175, 179, 183, 187, 191, 195
OFFSET
1,1
EXAMPLE
a(2) = ceiling( (1*2^0 + 1*2^1 + 2*2^2 + 4*2^3)/(1*2^0 + 2*2^1 + 1*2^2) ) = ceiling(43/9) = ceiling(4.7777...) = 5.
MATHEMATICA
Table[Ceiling[(1+n+2n^2+4n^3)/(1+2n+n^2)], {n, 50}] (* Harvey P. Dale, Aug 11 2019 *)
PROG
(PARI) a(n) = ceil((1 + n + 2*n^2 + 4*n^3)/(1 + 2*n + n^2)); \\ Michel Marcus, Aug 31 2013
CROSSREFS
Cf. A086790.
Sequence in context: A190506 A047385 A284624 * A211274 A276217 A354835
KEYWORD
nonn,easy
AUTHOR
Wang Dan (wangdan01(AT)lycos.com), Aug 06 2003
STATUS
approved