|
| |
|
|
A104891
|
|
a(0) = 0; a(n) = 5*a(n-1) + 5.
|
|
1
| |
|
|
0, 5, 30, 155, 780, 3905, 19530, 97655, 488280, 2441405, 12207030, 61035155, 305175780, 1525878905, 7629394530, 38146972655, 190734863280, 953674316405, 4768371582030
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
COMMENTS
| Conjectured to be the 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 (maxale(AT)gmail.com), Jan 23 2006
|
|
|
FORMULA
| a(n) = (5^(n+1) - 5) / 4 - Max Alekseyev (maxale(AT)gmail.com), Jan 23 2006
a(n) = 5^n+a(n-1) (with a(0)=0). [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 13 2010]
|
|
|
EXAMPLE
| a(3) = 5*a(2) + 5 = 5*30 + 5 = 155.
|
|
|
MAPLE
| a:=n->sum (5^j, j=1..n): seq(a(n), n=0..18); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 27 2007
|
|
|
CROSSREFS
| Cf. A052386, A052379, A080674, A029858, A000918, A000225.
Sequence in context: A080951 A180285 A055298 * A110155 A122995 A003731
Adjacent sequences: A104888 A104889 A104890 * A104892 A104893 A104894
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Alexandre Wajnberg (alexandre.wajnberg(AT)ulb.ac.be), Apr 24 2005
|
| |
|
|
