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A194138
a(n) = Sum_{j=1..n} floor(j*(1+sqrt(2))), n-th partial sum of Beatty sequence for 1+sqrt(2).
1
2, 6, 13, 22, 34, 48, 64, 83, 104, 128, 154, 182, 213, 246, 282, 320, 361, 404, 449, 497, 547, 600, 655, 712, 772, 834, 899, 966, 1036, 1108, 1182, 1259, 1338, 1420, 1504, 1590, 1679, 1770, 1864, 1960, 2058, 2159, 2262, 2368, 2476, 2587, 2700, 2815
OFFSET
1,1
LINKS
MATHEMATICA
c[n_] := Sum[Floor[j*(1+Sqrt[2])], {j, 1, n}];
c = Table[c[n], {n, 1, 90}]
PROG
(PARI) for(n=1, 60, print1(sum(j=1, n, floor(j*(1+sqrt(2)))), ", ")) \\ G. C. Greubel, Oct 05 2018
(Magma) [(&+[Floor(k*(1+Sqrt(2))): k in [1..n]]): n in [1..60]] // G. C. Greubel, Oct 05 2018
CROSSREFS
Cf. A003151 (Beatty sequence for 1+sqrt(2)).
Sequence in context: A230537 A267874 A194143 * A194137 A226292 A026052
KEYWORD
nonn
AUTHOR
Clark Kimberling, Aug 17 2011
STATUS
approved