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A130165
a(1)=1; a(n)=prime(mod(a(n-1),10)).
0
1, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2, 3, 5, 11, 2
OFFSET
1,2
COMMENTS
Starting with the second term, cycles every four terms.
Not the same sequence as a(1)=1; a(n)=mod(prime(a(n-1)),10).
FORMULA
a(1)=1; a(n)=prime(mod(a(n-1),10)).
G.f.: x -x^2*(2+3*x+5*x^2+11*x^3) / ( (x-1)*(1+x)*(1+x^2) ). - R. J. Mathar, Jun 20 2021
MATHEMATICA
f[s_List] := Block[{}, Append[s, Prime@ Last@ Mod[s, 10]]]; Nest[f, {1}, 93]
CROSSREFS
Sequence in context: A154956 A197312 A259387 * A083397 A067362 A364201
KEYWORD
nonn,less,easy
AUTHOR
Robert G. Wilson v, May 13 2007
EXTENSIONS
NAME adapted to offset. - R. J. Mathar, Jun 20 2021
STATUS
approved