A058634 a(n) = floor(b(n)), where b(n) = 1/cos(b(n-1)), b(0) = 1.

1, 1, -4, -2, 2, -2, 9, -2, 1, -4, -2, 1, -4, -2, 1, -4, -2, 1, -3, -2, 1, -3, -2, 1, -4, -2, 1, -4, -2, 2, -2, 12, 1, 1, -4, -2, 1, -3, -2, 2, -2, 8, -3, -2, -6, 1, 16, -3, -2, 7, -12, 1, -4, -2, 2, -3, -3, -3, -2, -6, 1, 2, -2, 2, -3, -2, -6, 1, 4, -3, -2, 9, -2, 2, -3, -2, -4, -2, 1, -3, -2, 1, -3, -2, 2, -3, -2, -7, 1, 4, -2, 70, 4, -2, 27

Offset: 0

Author

Avi Peretz (njk(AT)netvision.net.il), Dec 26 2000

Keywords

• sign

Examples

			a(3) = -2 because: b(0) = 1, b(1) = 1/cos(1) = 1.850815..., b(2) = 1/cos(1.850815) = -3.618291..., b(3) = 1/cos(-3.618291) = -1.125468... and a(3) = floor(b(3)) = -2
		

Crossrefs

Cf. A000319.

Programs

PARI

default(realprecision,1000); b=1; for(n=0, 94, print1(floor(b)", "); b=1/cos(b))

Extensions

More terms from Ralf Stephan, Mar 23 2003