|
| |
| |
|
|
|
1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4, 1, 7, 4
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
COMMENTS
| Also the digital root of 7^n. If we convert this to a repeating decimal 0.174174.., we get the rational number 58/333. - Cino Hilliard (hillcino368(AT)gmail.com), Dec 31 2004
A141722 (1, 25, 121, 505, 2041, 8185) mod 9 . Note A141722=10*A000975(2n)+A000975(2n+1). [From Paul Curtz (bpcrtz(AT)free.fr), Sep 15 2008]
|
|
|
FORMULA
| a(n)=(1/3)*{7*(n mod 3)+7*[(n+1) mod 3]-2*[(n+2) mod 3]}, with n>=0 [From Paolo P. Lava (paoloplava(AT)gmail.com), Oct 21 2008]
G.f.: (1+7x+4x^2)/((1-x)(1+x+x^2)). a(n+1)-a(n)=3*A099837(n+3). a(n)=4-3*A049347(n). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 23 2009]
a(n)=4+4/3*(-1/2-(1/2*I)*sqrt(3))^(-2)*(-1/2-(1/2*I)*sqrt(3))^n+4/3*(-1/2+(1/2*I) *sqrt(3))^(-2)*(-1/2+(1/2*I)*sqrt(3))^n+1/3*(-1/2-(1/2*I)*sqrt(3))^n+1/3*(-1/2 +(1/2*I)*sqrt(3))^n+7/3*(-1/2-(1/2*I)*sqrt(3))^(-1)*(-1/2-(1/2*I)*sqrt(3))^n+7/3 *(-1/2+(1/2*I)*sqrt(3))^(-1)*(-1/2+(1/2*I)*sqrt(3))^n, with n>=0 and I=sqrt(-1) [From Paolo P. Lava (paoloplava(AT)gmail.com), Feb 25 2010]
|
|
|
MATHEMATICA
| Table[PowerMod[7, n, 9], {n, 0, 200}] (* From Vladimir Joseph Stephan Orlovsky, Jun 10 2011 *)
|
|
|
PROG
| (Other) sage: [power_mod(7, n, 9)for n in xrange(0, 105)] # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Nov 03 2009]
(MAGMA)[7^n mod 9: n in [0..80]]; [From Vincenzo Librandi, Feb 07 2011]
|
|
|
CROSSREFS
| Sequence in context: A010138 A199157 A010508 * A144468 A059630 A011407
Adjacent sequences: A070400 A070401 A070402 * A070404 A070405 A070406
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), May 12 2002
|
| |
|
|
