A034108 Fractional part of square root of a(n) starts with 2: first term of runs.

5, 18, 28, 39, 52, 68, 85, 105, 126, 149, 175, 202, 232, 263, 296, 332, 369, 409, 450, 493, 539, 586, 636, 687, 740, 796, 853, 913, 974, 1037, 1103, 1170, 1240, 1311, 1384, 1460, 1537, 1617, 1698, 1781, 1867, 1954, 2044, 2135, 2228, 2324, 2421, 2521, 2622

Offset

1,1

Links

Table of n, a(n) for n=1..49.

Formula

Conjectures from Chai Wah Wu, Apr 14 2024: (Start)

a(n) = 2*a(n-1) - a(n-2) + a(n-5) - 2*a(n-6) + a(n-7) for n > 8.

G.f.: x*(-6*x^7 + 7*x^6 + 2*x^5 - 2*x^4 - x^3 + 3*x^2 - 8*x - 5)/((x - 1)^3*(x^4 + x^3 + x^2 + x + 1)). (End)

Crossrefs

Cf. A034098.

Sequence in context: A035338 A055371 A034098 * A155450 A322409 A287894

Adjacent sequences: A034105 A034106 A034107 * A034109 A034110 A034111

Keyword

nonn,base,changed

Author

Patrick De Geest, Sep 15 1998

Extensions

Offset 1 from Alois P. Heinz, Aug 05 2020

Status

approved