login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A071283
Numerators of Peirce sequence of order 4.
0
0, 0, 0, 0, 1, 1, 2, 1, 2, 3, 2, 4, 3, 1, 5, 4, 6, 3, 5, 7, 4, 8, 6, 2, 9, 7, 10, 5, 8, 11, 6, 12, 9, 3, 13, 10, 14, 7, 11, 15, 8, 16, 12, 4, 17, 13, 18, 9, 14, 19, 10, 20, 15, 5, 21, 16, 22, 11, 17, 23, 12, 24, 18, 6, 25, 19, 26, 13, 20, 27, 14, 28, 21, 7, 29, 22, 30, 15, 23, 31
OFFSET
0,7
REFERENCES
R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics, Addison-Wesley, Reading, MA, 2nd ed. 1998, p. 151.
FORMULA
Conjectures from Colin Barker, Mar 29 2017: (Start)
G.f.: x^4*(x^19 + x^18 + x^17 + 2*x^16 + 2*x^15 + 3*x^14 + x^13 + 3*x^12 + 4*x^11 + 2*x^10 + 3*x^9 + 2*x^8 + x^7 + 2*x^6 + x^5 + x^4)/(x^20 - 2*x^10 + 1).
a(n) = 2*a(n-10) - a(n-20) for n>19.
(End)
EXAMPLE
The Peirce sequences of orders 1, 2, 3, 4, 5 begin:
0/1 1/1 2/1 3/1 4/1 5/1 6/1 7/1 ...
0/2 0/1 1/2 2/2 1/1 3/2 4/2 2/1 ... (numerators are A009947)
0/2 0/3 0/1 1/3 1/2 2/3 2/2 3/3 ...
0/2 0/4 0/3 0/1 1/4 1/3 2/4 1/2 ...
0/2 0/4 0/5 0/3 0/1 1/5 1/4 1/3 ...
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
N. J. A. Sloane, Jun 11 2002
EXTENSIONS
More terms from Reiner Martin, Oct 15 2002
STATUS
approved