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1,2

Table of n, a(n) for n=1..11.

maybe a(1)=1 a(2)=2, a(n)=f(n-1) where f is A005097.

a(6)=6 because X^6 (mod 13) is +-1.

Cf. A002322, A005097.

Sequence in context: A236970 A060966 A172993 * A035631 A050046 A052337

Adjacent sequences: A135276 A135277 A135278 * A135280 A135281 A135282

more,nonn

Masahiko Shin, Dec 02 2007

Edited by R. J. Mathar, Jan 30 2008

approved