

A102822


a(n+1) = integer part of Sqrt(2a(n)^2).


1



3, 4, 5, 7, 9, 12, 16, 22, 31, 43, 60, 84, 118, 166, 234, 330, 466, 659, 931, 1316, 1861, 2631, 3720, 5260, 7438, 10518, 14874, 21035, 29747, 42068, 59493, 84135, 118984, 168268, 237966, 336534, 475930, 673066, 951859, 1346131, 1903716, 2692260
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OFFSET

3,1


COMMENTS

A square of side a(n) has a(n+1) as integer part of its diagonal.  Robert G. Wilson v, Mar 03 2005
Starting the sequence with 0, 1 or 2 would be rather dull.


LINKS

Harvey P. Dale, Table of n, a(n) for n = 3..1000


EXAMPLE

A 3 X 3 square has a diagonal of 4.242640687119285...; int. part is "4";
a 4 X 4 square has a diagonal of 5.656854249492381...; int. part is "5";
a 5 X 5 square has a diagonal of 7.071067811865475...; int. part is "7";
a 7 X 7 square has a diagonal of 9.899494936611665...; int. part is "9";
a 9 X 9 square, etc.


MATHEMATICA

NestList[ Function[x, IntegerPart[ Sqrt[ 2x^2]]], 3, 30] (* Robert G. Wilson v, Mar 03 2005 *)
NestList[IntegerPart[Sqrt[2#^2]]&, 3, 50] (* Harvey P. Dale, Mar 20 2018 *)


CROSSREFS

Sequence in context: A035249 A104805 A260996 * A167159 A226918 A227391
Adjacent sequences: A102819 A102820 A102821 * A102823 A102824 A102825


KEYWORD

base,easy,nonn


AUTHOR

Eric Angelini, Feb 27 2005


EXTENSIONS

More terms from Robert G. Wilson v, Mar 03 2005


STATUS

approved



