This site is supported by donations to The OEIS Foundation.

The October issue of the Notices of the Amer. Math. Soc. has an article about the OEIS.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A284621 Positions of 0 in A284620. 2
 1, 5, 11, 15, 21, 27, 31, 37, 41, 47, 53, 57, 63, 69, 73, 79, 83, 89, 95, 99, 105, 109, 115, 121, 125, 131, 137, 141, 147, 151, 157, 163, 167, 173, 179, 183, 189, 193, 199, 205, 209, 215, 219, 225, 231, 235, 241, 247, 251, 257, 261, 267, 273, 277, 283, 287 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence and A005843 and A130568 partition the positive integers into sequences with slopes t = 1+sqrt(5), u = 3+sqrt(5), v = 2, where 1/t + 1/u + 1/v = 1.  The positions of 1 in A284620 are given by A005843, and of 2, by A130568. LINKS Clark Kimberling, Table of n, a(n) for n = 1..10000 FORMULA a(n)  = 1 + 2*A001950(n-1) for n >= 1. EXAMPLE As a word, A284620 = 012101212101210121..., in which 0 is in positions 1,5,11,15,... MATHEMATICA s = Nest[Flatten[# /. {0 -> {0, 1}, 1 -> {0}}] &, {0}, 13]  (* A003849 *) w = StringJoin[Map[ToString, s]] w1 = StringReplace[w, {"00" -> "2"}] st = ToCharacterCode[w1] - 48 (* A284620 *) Flatten[Position[st, 0]]  (* A284621 *) Flatten[Position[st, 1]]  (* A005843 *) Flatten[Position[st, 2]]  (* A130568 *) CROSSREFS Cf. A005843, A130568, A284620. Sequence in context: A314053 A314054 A314055 * A314056 A314057 A314058 Adjacent sequences:  A284618 A284619 A284620 * A284622 A284623 A284624 KEYWORD nonn,easy AUTHOR Clark Kimberling, May 02 2017 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 22 20:30 EDT 2018. Contains 315270 sequences. (Running on oeis4.)