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A180450
Primes of the form floor( (n^sqrt(2) + n)/sqrt(2) ).
1
3, 5, 7, 13, 19, 43, 67, 71, 89, 103, 107, 127, 137, 163, 191, 311, 317, 337, 383, 397, 431, 547, 569, 577, 599, 607, 653, 661, 677, 701, 709, 733, 757, 823, 857, 977, 1021, 1039, 1129, 1193, 1249, 1277, 1381, 1459, 1699, 1709, 1823, 1949, 2099, 2131, 2153, 2521, 2647
OFFSET
1,1
COMMENTS
Intersection of A000040 with the sequence 1, 3, 5, 7, 10, 13, 16, 19, 22, 25, 28, 32, 35, ... defined by the floor function.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
MAPLE
select(isprime, [seq(floor((n^sqrt(2)+n)/sqrt(2)), n=1..350)]); # Muniru A Asiru, Sep 29 2018
MATHEMATICA
Select[With[{b = Sqrt[2]}, Table[Floor[(n^b + n)/b], {n, 500}]], PrimeQ] (* G. C. Greubel, Sep 29 2018 *)
PROG
(PARI) for(n=1, 148438, if(ispseudoprime(t=floor((n^sqrt(2)+n)/sqrt(2))), print1(t", "))); v \\ Charles R Greathouse IV, Feb 18 2011
CROSSREFS
Sequence in context: A330222 A154700 A187872 * A051507 A173145 A347834
KEYWORD
easy,nonn
AUTHOR
William A. Tedeschi, Sep 07 2010
EXTENSIONS
Formula replaced by a comment - R. J. Mathar, Sep 09 2010
STATUS
approved