OFFSET
1,1
COMMENTS
18656380 = 2^2*5*932819, 20522060 = 2^2*5*13*17*4643, 28630036 = 2^2*19*449*839, 24289964 = 2^2*97*62603.
The cycle was discovered by Cohen (1970). - Amiram Eldar, Aug 18 2024
LINKS
Henri Cohen, On amicable and sociable numbers, Math. Comp., Vol. 24, No. 110 (1970), pp. 423-429.
Index entries for linear recurrences with constant coefficients, signature (0,0,0,1).
PROG
(PARI) a(n)=[24289964, 18656380, 20522060, 28630036][n%4+1] \\ Charles R Greathouse IV, Feb 19 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Miklos Kristof, Aug 22 2002
STATUS
approved