The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A128664 Rounded first term of asymptotic approximation to A003823. 0
 1, 1, 0, -1, 0, 1, 1, -1, -2, 0, 2, 2, -1, -3, -1, 3, 3, -2, -5, -1, 5, 5, -3, -8, -2, 8, 8, -5, -12, -2, 13, 11, -7, -18, -4, 18, 17, -10, -26, -5, 27, 24, -15, -37, -7, 38, 33, -21, -52, -10, 52, 46, -29, -72, -14, 72, 64, -40, -98, -20, 98, 87, -54, -133, -27, 132, 116, -72, -178, -36, 176, 155, -96, -236, -47, 233, 205, -126 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,9 REFERENCES B. Cais and B. Conrad, Modular curves and Ramanujan's continued fraction, J. Reine Angew. Math. 597 (2006), 27-104. See page 69 (7.27). MR2264315 LINKS PROG (PARI) {a(n)= if(n<1, n==0, round( 4/5*Pi/ sqrt(5*n-1)* cos(2/25*Pi* (5*n-2))* besseli(1, 4/25*Pi* sqrt(5*n-1))) )} CROSSREFS Sequence in context: A156643 A308626 A268755 * A003823 A059451 A083817 Adjacent sequences:  A128661 A128662 A128663 * A128665 A128666 A128667 KEYWORD sign AUTHOR Michael Somos, Mar 19 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 3 16:20 EST 2020. Contains 338906 sequences. (Running on oeis4.)