OFFSET
0,4
COMMENTS
36m^2+24m+7=(6m+2)^2+3 which is three more than a square
FORMULA
36*a(n)^2+24*a(n)+7=A049423(n+1).
EXAMPLE
a(3)=-2 since 36*(-2)^2+24*(-2)+7=144-48+7=103 which is prime
CROSSREFS
KEYWORD
sign
AUTHOR
Henry Bottomley, Jul 06 2000
STATUS
approved