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A017401
a(n) = 11n + 1.
12
1, 12, 23, 34, 45, 56, 67, 78, 89, 100, 111, 122, 133, 144, 155, 166, 177, 188, 199, 210, 221, 232, 243, 254, 265, 276, 287, 298, 309, 320, 331, 342, 353, 364, 375, 386, 397, 408, 419, 430, 441, 452, 463, 474, 485, 496, 507, 518, 529, 540, 551, 562, 573, 584, 595, 606, 617, 628, 639, 650, 661
OFFSET
0,2
COMMENTS
Let A be the Hessenberg matrix of order n, defined by: A[1,j]=1, A[i,i]:=11, (i>1), A[i,i-1]=-1, and A[i,j]=0 otherwise. Then, for n>=2, a(n-1)=-charpoly(A,x^(n-1)). - Milan Janjic, Feb 21 2010
Sequence lists all nonnegative solutions to x^k == 1 (mod 11), where k is a member of A045572. - Bruno Berselli, Jan 18 2016
FORMULA
G.f.: (1+10*x)/(1-x)^2.
E.g.f.: exp(x)*(1 + 11*x). - Stefano Spezia, Oct 08 2022
MATHEMATICA
Range[1, 1000, 11] (* Vladimir Joseph Stephan Orlovsky, May 28 2011 *)
PROG
(Magma) [11*n+1: n in [0..60]]; // Vincenzo Librandi, Jul 30 2011
(PARI) a(n)=11*n+1 \\ Charles R Greathouse IV, Jan 18 2016
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved