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A087055 Largest square number less than 2*n^2. 6
1, 4, 16, 25, 49, 64, 81, 121, 144, 196, 225, 256, 324, 361, 441, 484, 576, 625, 676, 784, 841, 961, 1024, 1089, 1225, 1296, 1444, 1521, 1681, 1764, 1849, 2025, 2116, 2304, 2401, 2500, 2704, 2809, 3025, 3136, 3249, 3481, 3600, 3844, 3969, 4225, 4356, 4489 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = A001951(n)^2 = floor(n*sqrt(2))^2.
EXAMPLE
a(10) = 196 because 196 is the largest square less than 2*10^2 = 200.
MATHEMATICA
Table[Floor[Sqrt[2n^2-1]], {n, 100}]^2 (* Harvey P. Dale, Mar 26 2011 *)
PROG
(PARI) a(n) = sqrtint(2*n^2)^2; \\ Michel Marcus, Jul 08 2020
CROSSREFS
Sequence in context: A350835 A214937 A235001 * A135556 A163095 A075576
KEYWORD
easy,nonn
AUTHOR
Jens Voß, Aug 07 2003
STATUS
approved

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Last modified April 21 07:21 EDT 2024. Contains 371850 sequences. (Running on oeis4.)