

A106250


Expansion of (1x+x^2+x^3)/(1xx^5+x^6).


1



1, 0, 1, 2, 2, 3, 2, 3, 4, 4, 5, 4, 5, 6, 6, 7, 6, 7, 8, 8, 9, 8, 9, 10, 10, 11, 10, 11, 12, 12, 13, 12, 13, 14, 14, 15, 14, 15, 16, 16, 17, 16, 17, 18, 18, 19, 18, 19, 20, 20, 21, 20, 21, 22, 22, 23, 22, 23, 24, 24, 25, 24, 25, 26, 26, 27, 26, 27, 28, 28, 29, 28, 29, 30, 30, 31, 30
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OFFSET

0,4


LINKS

Table of n, a(n) for n=0..76.
Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,1,1).


FORMULA

G.f.: (1x+x^2+x^3)/(1xx^5+x^6)=(1+x^2+2x^3+2x^4+x^5+2x^6+x^7)/(1x^5)^2; a(n)=sum{k=0..n, mu(k mod 5)}.


MATHEMATICA

CoefficientList[Series[(1x+x^2+x^3)/(1xx^5+x^6), {x, 0, 120}], x] (* or *) LinearRecurrence[{1, 0, 0, 0, 1, 1}, {1, 0, 1, 2, 2, 3}, 121] (* Harvey P. Dale, Apr 26 2011 *)


CROSSREFS

Cf. A008611.
Sequence in context: A087735 A277194 A172151 * A029248 A085916 A286535
Adjacent sequences: A106247 A106248 A106249 * A106251 A106252 A106253


KEYWORD

easy,nonn


AUTHOR

Paul Barry, Apr 27 2005


STATUS

approved



