OFFSET

1,1

EXAMPLE

a(1) = -2 because ((2*1)-th semiprime) - 2*(1st semiprime) = 6 - 2*4 = -2.

CROSSREFS

KEYWORD

sign

AUTHOR

Juri-Stepan Gerasimov, Jun 02 2010

EXTENSIONS

Entries checked by R. J. Mathar, Aug 12 2010

STATUS

approved