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A082532 a(n) = n^2 - 2*floor(n/sqrt(2))^2. 4
1, 2, 1, 8, 7, 4, 17, 14, 9, 2, 23, 16, 7, 34, 25, 14, 1, 36, 23, 8, 49, 34, 17, 64, 47, 28, 7, 62, 41, 18, 79, 56, 31, 4, 73, 46, 17, 92, 63, 32, 113, 82, 49, 14, 103, 68, 31, 126, 89, 50, 9, 112, 71, 28, 137, 94, 49, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = n^2 - 2*(A049472(n))^2. - R. J. Mathar, Mar 28 2011

EXAMPLE

a(3)=1 since 3^2 - 2*floor(3/1.4142..)^2 = 9 - 2*2^2 = 9 - 8 = 1.

MAPLE

A049472 := proc(n) floor(n/sqrt(2)) ; end proc:

A082532 := proc(n) n^2-2*A049472(n)^2 ; end proc:

seq(A082532(n), n=1..80) ; # R. J. Mathar, Mar 28 2011

MATHEMATICA

Table[n^2 - 2*Floor[n/Sqrt[2]]^2, {n, 1, 100}] (* G. C. Greubel, Jan 27 2018 *)

PROG

(PARI) for(n=1, 50, print1(n^2 - 2*floor(n/sqrt(2))^2, ", ")) \\ G. C. Greubel, Jan 27 2018

(MAGMA) [n^2 - 2*Floor(n/Sqrt(2))^2: n in [1..50]]; // G. C. Greubel, Jan 27 2018

CROSSREFS

a(n)=1 for n in A001541.

Sequence in context: A298641 A293415 A197018 * A049250 A060587 A168142

Adjacent sequences:  A082529 A082530 A082531 * A082533 A082534 A082535

KEYWORD

easy,nonn

AUTHOR

Carmine Suriano, May 01 2003

STATUS

approved

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Last modified September 24 01:21 EDT 2020. Contains 337315 sequences. (Running on oeis4.)