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A109366
a(-1)=0, a(0)=1 and recursively a(n) = prime(n)*(a(n-1)+a(n-2)).
2
1, 2, 9, 55, 448, 5533, 77753, 1415862, 28378685, 685274581, 20695944714, 662817798145, 25290008485783, 1064065877641048, 46842303103453733, 2251599342111454707, 121817407196390147320, 7320071385771594519593
OFFSET
0,2
MAPLE
A109366 := proc(n) if n<= 0 then n+1; else ithprime(n)*(procname(n-1)+procname(n-2)) ; end if; end proc:
seq(A109366(n), n=0..20) ; # R. J. Mathar, Sep 15 2011
CROSSREFS
Cf. A109365.
Sequence in context: A231172 A009363 A069564 * A303914 A241457 A229208
KEYWORD
nonn
AUTHOR
Giorgio Balzarotti, Aug 23 2005
STATUS
approved