login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A095238 a(1) = 1, a(n) = n*(sum of all previous terms mod n). 1
1, 2, 0, 12, 0, 18, 35, 32, 9, 90, 11, 72, 117, 98, 30, 240, 34, 162, 247, 200, 63, 462, 69, 288, 425, 338, 108, 756, 116, 450, 651, 512, 165, 1122, 175, 648, 925, 722, 234, 1560, 246, 882, 1247, 968, 315, 2070, 329, 1152, 1617, 1250, 408, 2652, 424, 1458, 2035 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

An open question is whether the sequence contains zeros except for the 3rd and the 5th number. I checked this up to a(10000), which happens to be 99990000. - Johan Claes, Jun 16 2004

LINKS

Table of n, a(n) for n=1..55.

FORMULA

Appears to satisfy a linear recurrence with characteristic polynomial (1+x)(1+x^3)^2(1-x^3)^3 (checked up to n = 10^4). - Ralf Stephan, Dec 04 2004

EXAMPLE

a(6) = 6*((1 + 2 + 0 + 12 + 0) mod 6) = 18.

MAPLE

A095238:=proc(n) option remember; n*(add(A095238(i), i=1..n-1) mod n) end: A095238(1):=1: seq(A095238(n), n=1..100);

MATHEMATICA

a[1] = 1; a[n_] := a[n] = n*Mod[Sum[a[i], {i, n - 1}], n]; Table[ a[n], {n, 55}] (* Robert G. Wilson v, Jun 16 2004 *)

PROG

(PARI) a=vector(1000); a[1]=1; for(i=2, 1000, a[i]=i*lift(Mod(sum(j=1, i-1, a[j]), i)))

CROSSREFS

Cf. A074143.

Sequence in context: A075533 A053814 A293260 * A167345 A292496 A285480

Adjacent sequences:  A095235 A095236 A095237 * A095239 A095240 A095241

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Jun 15 2004

EXTENSIONS

More terms from Alec Mihailovs (alec(AT)mihailovs.com), Robert G. Wilson v and Johan Claes, Jun 16 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 August 12 09:05 EDT 2020. Contains 336438 sequences. (Running on oeis4.)