OFFSET
0,4
COMMENTS
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
MATHEMATICA
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 *)
PROG
(PARI) lappf(n) = my(f=factor(n)); vecmax(vector(#f[, 1], i, f[i, 1]^f[i, 2]));
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
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Altug Alkan, Feb 08 2017
STATUS
approved