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A301687
Partial sums of A301686.
1
1, 6, 13, 27, 44, 63, 91, 120, 151, 193, 234, 277, 333, 386, 441, 511, 576, 643, 727, 804, 883, 981, 1070, 1161, 1273, 1374, 1477, 1603, 1716, 1831, 1971, 2096, 2223, 2377, 2514, 2653, 2821, 2970, 3121, 3303, 3464, 3627, 3823, 3996, 4171, 4381, 4566, 4753, 4977, 5174, 5373, 5611, 5820, 6031, 6283, 6504, 6727, 6993, 7226, 7461, 7741
OFFSET
0,2
COMMENTS
Linear recurrence and g.f. confirmed by Shutov/Maleev link in A301686. - Ray Chandler, Aug 30 2023
FORMULA
From Chai Wah Wu, Feb 03 2021: (Start)
a(n) = a(n-1) + 2*a(n-3) - 2*a(n-4) - a(n-6) + a(n-7) for n > 6.
G.f.: (-x^6 - 5*x^5 - 7*x^4 - 12*x^3 - 7*x^2 - 5*x - 1)/((x - 1)^3*(x^2 + x + 1)^2). (End)
CROSSREFS
Cf. A301686.
Sequence in context: A268721 A183337 A358244 * A173559 A086224 A116913
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 25 2018
STATUS
approved