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A338638
a(n) = L(L(n)) mod L(n), where L = Lucas numbers = A000032.
3
1, 0, 1, 3, 1, 1, 0, 1, 1, 7, 4, 1, 199, 1, 4, 843, 1, 1, 0, 1, 29, 123, 4, 1, 3, 199, 4, 39603, 29, 1, 5778, 1, 1, 7, 4, 17622890, 12752043, 1, 4, 39603, 7881196, 1, 5778, 1, 29, 7, 4, 1, 3, 1149851, 28143689044, 7, 29, 1, 0, 312119004790, 6643838879, 7, 4, 1
OFFSET
0,4
LINKS
FORMULA
a(n) = A005371(n) mod A000032(n).
a(n) = 0 for n in { A016089 }.
MAPLE
b:= proc(n) local r, M, p; r, M, p:=
<<1|0>, <0|1>>, <<0|1>, <1|1>>, n;
do if irem(p, 2, 'p')=1 then r:=
`if`(nargs=1, r.M, r.M mod args[2]) fi;
if p=0 then break fi; M:=
`if`(nargs=1, M.M, M.M mod args[2])
od; (r.<<2, 1>>)[1$2]
end:
a:= n-> (f-> b(f$2) mod f)(b(n)):
seq(a(n), n=0..60);
MATHEMATICA
Table[Mod[LucasL[LucasL[n]], LucasL[n]], {n, 0, 60}] (* Harvey P. Dale, Jul 04 2022 *)
KEYWORD
nonn,look
AUTHOR
Alois P. Heinz, Nov 04 2020
STATUS
approved