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A064776
a(n) is smallest number >= a(n-1) such that a(n) plus any set of the previous values of the sequence is a nonsquare.
2
2, 3, 3, 5, 21, 24, 24, 80, 80, 80, 480, 480, 720, 1200, 2000, 8400, 9600, 9600, 32000, 32000, 32000, 192000, 192000, 288000, 480000, 800000, 3360000, 3840000, 3840000, 12800000, 12800000, 12800000, 76800000, 76800000, 115200000, 192000000
OFFSET
1,1
COMMENTS
Why do so many terms end with a string of zeros? - Zak Seidov, Jan 01 2008
EXAMPLE
a(3) = 3 because possible sums are 3, 3+a(1), 3+a(2), 3+a(1)+a(2) = 3, 3+2, 3+3, 3+2+3 = 3,5,6,8, all of which are nonsquares.
CROSSREFS
Cf. A133662.
Cf. A133662.
Sequence in context: A154693 A065854 A263769 * A270592 A096659 A154695
KEYWORD
nonn
AUTHOR
Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 18 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), Oct 10 2003
More terms and better definition from Don Reble, Jan 01 2008
STATUS
approved