A282184 - OEIS

%I #16 Feb 10 2017 20:16:49

%S 1,1,1,3,5,9,17,31,19,67,13,11,13,37,61,37,27,125,27,179,331,179,53,

%T 563,53,223,839,223,257,1319,257,47,541,169,757,163,121,347,631,157,

%U 227,29,59,9,97,11,13,121,29,163,313,101,577,991,1669,83,211,151,89,41,281,137,27,89,23,139,251,59,449,23,59,59

%N a(n) = A034699(a(n-1) + a(n-2) + a(n-3)) with a(0) = a(1) = a(2) = 1.

%C Sequence is cyclical, beginning with terms a(255)-a(257) = {19,13,43} with a period of 306 terms. - _Michael De Vlieger_, Feb 08 2017

%e a(5) = 9 because A034699(1 + 3 + 5) = A034699(9) = 9.

%t a = {1, 1, 1}; Do[AppendTo[a, If[# == 1, 1, Max[Power @@@ FactorInteger@ #]] &@ Total@ {a[[i - 3]], a[[i - 2]], a[[i - 1]]}], {i, 4, 72}]; a (* _Michael De Vlieger_, Feb 08 2017 *)

%o (PARI) lappf(n) = my(f=factor(n)); vecmax(vector(#f[, 1], i, f[i, 1]^f[i, 2]));

%o lista(nn) = {x = 1; y = 1; z = 1; print1(x, ", ", y, ", ", z, ", "); for (n=4, nn, t = lappf(x+y+z); print1(t, ", "); x = y; y = z; z = t;);} \\ _Michel Marcus_, Feb 10 2017

%Y Cf. A000213, A034699, A177904, A282098.

%K nonn,easy

%O 0,4

%A _Altug Alkan_, Feb 08 2017