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A104891 a(0) = 0; a(n) = 5*a(n-1) + 5. 2
0, 5, 30, 155, 780, 3905, 19530, 97655, 488280, 2441405, 12207030, 61035155, 305175780, 1525878905, 7629394530, 38146972655, 190734863280, 953674316405, 4768371582030, 23841857910155, 119209289550780, 596046447753905, 2980232238769530, 14901161193847655 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Number of integers from 0 to (10^n)-1 that lack 0, 1, 2, 3 and 4 as a digit.

Number of monic irreducible polynomials of degree 1 in GF(5)[x1,...,xn]. - Max Alekseyev, Jan 23 2006

LINKS

Table of n, a(n) for n=0..23.

Index entries for linear recurrences with constant coefficients, signature (6,-5).

FORMULA

a(n) = (5^(n+1) - 5) / 4. - Max Alekseyev, Jan 23 2006

a(n) = 5^n+a(n-1) (with a(0)=0). - Vincenzo Librandi, Nov 13 2010

a(n) = 6*a(n-1)-5*a(n-2). G.f.: 5*x / ((x-1)*(5*x-1)). - Colin Barker, Jul 25 2014

EXAMPLE

a(3) = 5*a(2) + 5 = 5*30 + 5 = 155.

MAPLE

a:=n->add(5^j, j=1..n): seq(a(n), n=0..30); # Zerinvary Lajos, Jun 27 2007

MATHEMATICA

RecurrenceTable[{a[n]==5*a[n-1]+5, a[0]==0}, a, {n, 0, 20}] (* Vaclav Kotesovec, Jul 25 2014 *)

PROG

(PARI) concat(0, Vec(5*x/((x-1)*(5*x-1)) + O(x^100))) \\ Colin Barker, Jul 25 2014

CROSSREFS

Cf. A052386, A052379, A080674, A029858, A000918, A000225.

Row n=5 of A228275.

Sequence in context: A282086 A180285 A055298 * A246937 A110155 A122995

Adjacent sequences:  A104888 A104889 A104890 * A104892 A104893 A104894

KEYWORD

easy,nonn

AUTHOR

Alexandre Wajnberg, Apr 24 2005

STATUS

approved

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Last modified May 20 20:16 EDT 2019. Contains 323426 sequences. (Running on oeis4.)