A290371 Integers k such that f(k) - f(k-1) equals 1, where f(n) = floor(n/exp(sqrt(log(n)))).

3, 9, 16, 24, 33, 42, 51, 61, 71, 82, 93, 104, 115, 127, 139, 151, 163, 175, 188, 200, 213, 226, 239, 253, 266, 279, 293, 307, 321, 335, 349, 363, 377, 392, 406, 421, 436, 451, 465, 480, 495, 511, 526, 541, 557, 572, 588, 603, 619, 635, 650, 666, 682, 698, 714, 730

Offset

1,1

Links

Table of n, a(n) for n=1..56.

J. M. De Koninck and V. Ouellet, On the n-th element of a set of positive integers, Annales Univ. Sci. Budapest Sect. Comput. 44 (2015), 153-164. See 3. on p. 162.

Mathematica

f[n_]:=Floor[n/Exp[Sqrt[Log[n]]]]; Select[Range[2, 1000], f[#] - f[# - 1]==1 &] (* Indranil Ghosh, Jul 28 2017 *)

Prog

(PARI) f(n) = floor(n/exp(sqrt(log(n))));
isok(n) = f(n) - f(n-1) == 1;
(Python)
from sympy import floor, exp, sqrt, log
def f(n): return floor(n/exp(sqrt(log(n))))
print([n for n in range(2, 1001) if f(n) - f(n - 1) == 1]) # Indranil Ghosh, Jul 28 2017

Crossrefs

Sequence in context: A338020 A020967 A253547 * A334563 A109340 A339918

Adjacent sequences: A290368 A290369 A290370 * A290372 A290373 A290374

Keyword

nonn

Author

Michel Marcus, Jul 28 2017

Status

approved