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 A089607 a(n)=((-1)^(n+1)*A002425(n)) modulo 4. 1
 1, 3, 1, 3, 3, 1, 1, 3, 3, 3, 1, 1, 3, 1, 1, 3, 3, 3, 1, 3, 3, 1, 1, 1, 3, 3, 1, 1, 3, 1, 1, 3, 3, 3, 1, 3, 3, 1, 1, 3, 3, 3, 1, 1, 3, 1, 1, 1, 3, 3, 1, 3, 3, 1, 1, 1, 3, 3, 1, 1, 3, 1, 1, 3, 3, 3, 1, 3, 3, 1, 1, 3, 3, 3, 1, 1, 3, 1, 1, 3, 3, 3, 1, 3, 3, 1, 1, 1, 3, 3, 1, 1, 3, 1, 1, 1, 3, 3, 1, 3, 3, 1, 1, 3, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(1)=1; for n>=2, a(n) = 2*A014577(n-1)+1 PROG (PARI) a(n)=numerator(2/n*(4^n-1)*bernfrac(2*n))%4 CROSSREFS Cf. A056832. Sequence in context: A122567 A122431 A279340 * A216637 A234308 A050141 Adjacent sequences:  A089604 A089605 A089606 * A089608 A089609 A089610 KEYWORD nonn AUTHOR Benoit Cloitre, Dec 30 2003 STATUS approved

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Last modified June 20 09:27 EDT 2019. Contains 324234 sequences. (Running on oeis4.)