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A108105
2^floor(n/5).
1
1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 16, 16, 16, 16, 16, 32, 32, 32, 32, 32, 64, 64, 64, 64, 64, 128, 128, 128, 128, 128, 256, 256, 256, 256, 256, 512, 512, 512, 512, 512, 1024
OFFSET
0,6
FORMULA
G.f.: (1+x+x^2+x^3+x^4)/(1-2*x^5).
MATHEMATICA
s[1] = {2}; s[2] = {3}; s[3] = {4}; s[4] = {5}; s[5] = {1, 6}; s[6] = {2}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]] a0 = Table[Length[p[i]], {i, 0, 50}]
PROG
(PARI) a(n)=2^(n\5) \\ Charles R Greathouse IV, Oct 03 2016
CROSSREFS
Sequence in context: A169718 A001306 A260984 * A321213 A063468 A010336
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Jun 03 2005
STATUS
approved