login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A099551 Odd part of n modulo 10. Final digit of A000265(n). 9
1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 1, 3, 3, 7, 5, 1, 7, 9, 9, 5, 1, 1, 3, 3, 5, 3, 7, 7, 9, 5, 1, 1, 3, 7, 5, 9, 7, 9, 9, 5, 1, 1, 3, 1, 5, 3, 7, 3, 9, 5, 1, 3, 3, 7, 5, 7, 7, 9, 9, 5, 1, 1, 3, 1, 5, 3, 7, 7, 9, 5, 1, 9, 3, 7, 5, 9, 7, 9, 9, 5, 1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 1, 3, 3, 7, 5, 3, 7, 9, 9, 5, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

G.f. g(x) satisfies: g(x) = g(x^2) + (x + 3*x^3 + 5*x^5 + 7*x^7 + 9*x^9)/(1-x^10). - Robert Israel, Aug 10 2018

MAPLE

f:= n -> n/2^padic:-ordp(n, 2) mod 10:

map(f, [$1..200]); # Robert Israel, Aug 10 2018

MATHEMATICA

Mod[Table[Max[Select[Divisors[n], OddQ]], {n, 110}], 10] (* Harvey P. Dale, Jun 22 2017 *)

PROG

(PARI) a(n)=(n>>valuation(n, 2))%10 \\ Charles R Greathouse IV, Dec 28 2012

CROSSREFS

Equals A010879( A000265(n) ).

Cf. A099544, A099545, A099546, A099547, A099548, A099549, A099550.

Sequence in context: A081431 A053641 A161825 * A211206 A036233 A145799

Adjacent sequences:  A099548 A099549 A099550 * A099552 A099553 A099554

KEYWORD

nonn,base,easy

AUTHOR

Ralf Stephan, Oct 23 2004

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 17 18:24 EST 2019. Contains 329241 sequences. (Running on oeis4.)