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A282098
a(n) = A006530(a(n-1)) + A006530(a(n-2)) + A006530(a(n-3)) with a(0) = a(1) = a(2) = 1.
2
1, 1, 1, 3, 5, 9, 11, 19, 33, 41, 71, 123, 153, 129, 101, 161, 167, 291, 287, 305, 199, 301, 303, 343, 151, 259, 195, 201, 117, 93, 111, 81, 71, 111, 111, 145, 103, 169, 145, 145, 71, 129, 143, 127, 183, 201, 255, 145, 113, 159, 195, 179, 245, 199, 385, 217, 241, 283, 555, 561, 337, 391, 377, 389, 441
OFFSET
0,4
COMMENTS
See also graph of this sequence.
LINKS
FORMULA
a(n) = a(n+212) for n >= 89. - Robert Israel, Feb 06 2017
EXAMPLE
a(6) = 11 because A006530(3) + A006530(5) + A006530(9) = 3 + 5 + 3 = 11.
MAPLE
for i from 0 to 2 do A[i]:= 1: G[i]:= 1 od:
for i from 3 to 303 do
A[i]:= G[i-1]+G[i-2]+G[i-3];
G[i]:= max(numtheory:-factorset(A[i]));
od:
seq(A[i], i=1..303); # Robert Israel, Feb 06 2017
MATHEMATICA
a[0] = a[1] = a[2] = 1; a[n_] := a[n] = FactorInteger[a[n - 1]][[-1, 1]] + FactorInteger[a[n - 2]][[-1, 1]] + FactorInteger[a[n - 3]][[-1, 1]]; Table[a@ n, {n, 0, 64}] (* Michael De Vlieger, Feb 07 2017 *)
CROSSREFS
KEYWORD
nonn,easy,look
AUTHOR
Altug Alkan, Feb 06 2017
STATUS
approved