A039975 An example of a d-perfect sequence: a(n) = A006318(n-1) mod 3.

1, 2, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..11000

D. Kohel, S. Ling and C. Xing, Explicit Sequence Expansions, in Sequences and their Applications, C. Ding, T. Helleseth, and H. Niederreiter, eds., Proceedings of SETA'98 (Singapore, 1998), 308-317, 1999. DOI: 10.1007/978-1-4471-0551-0_23

Formula

a(n) = A006318(n-1) mod 3. - Christian G. Bower, Jun 12 2005

Prog

(PARI)
A006318(n) = if( n<1, 1, sum( k=0, n, 2^k * binomial( n, k) * binomial( n, k-1)) / n);
A039975(n) = (A006318(n-1) % 3); \\ Antti Karttunen, Feb 13 2019

Crossrefs

Cf. A006318.

Cf. also A039969.

Sequence in context: A309938 A140581 A137277 * A358679 A016253 A286998

Adjacent sequences: A039972 A039973 A039974 * A039976 A039977 A039978

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

More terms from Christian G. Bower, Jun 12 2005

Bower's formula added to the name by Antti Karttunen, Feb 13 2019

Status

approved