Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A090678
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A090678 A088567 mod 2. +0
5
1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0 (list; graph; listen)
OFFSET

0,1

COMMENT

a(n) = -(-1)^[n/2]*A110036(n)/2 for n>=2, where A110036 gives the partial quotients of the continued fraction expansion of 1 + Sum_{n>=0} 1/x^(2^n). - Paul D. Hanna (pauldhanna(AT)juno.com), Jul 09 2005

REFERENCES

O. J. Rodseth and J. A. Sellers, On a Restricted m-Non-Squashing Partition Function, Journal of Integer Sequences, Vol. 8 (2005), Article 05.5.4.

LINKS

N. J. A. Sloane and J. A. Sellers, On non-squashing partitions, Discrete Math., 294 (2005), 259-274.

FORMULA

b(0) == 1; if n is odd, b(n) == b(n-1) + 1; b(8m+2) == 1; b(8m+6) == 0; b(16m+4) == 0; b(16m+12) == 1; for m>0, b(16m) == b(8m), b(32m+8) == 0, b(32m+24) == 1. In other words, for m>0, b(8m) is the value of the bit immediately to the left of the rightmost 1 when m is written in binary.

a(n) = (-1)^[n/2]*A110037(n). - Paul D. Hanna (pauldhanna(AT)juno.com), Jul 09 2005

PROGRAM

(PARI) {a(n)=(-1)^(n\2)*polcoeff(A=1+x-x^2*(1+x)/(1+x^2)+ sum(k=1, #binary(n), x^(3*2^(k-1))/prod(j=0, k, 1+x^(2^j)+x*O(x^n))), n)} (Hanna)

CROSSREFS

b(8m) is (apart from the first term) A038189(m).

Cf. A110036, A110037.

Adjacent sequences: A090675 A090676 A090677 this_sequence A090679 A090680 A090681

Sequence in context: A115356 A115359 A117906 this_sequence A110037 A128810 A123272

KEYWORD

nonn

AUTHOR

njas, Dec 20 2003

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified October 10 20:39 EDT 2008. Contains 144831 sequences.


AT&T Labs Research