This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A246011 a(n) = Product_{i in row n of A245562} Lucas(i+1), where Lucas = A000204. 1
 1, 3, 3, 4, 3, 9, 4, 7, 3, 9, 9, 12, 4, 12, 7, 11, 3, 9, 9, 12, 9, 27, 12, 21, 4, 12, 12, 16, 7, 21, 11, 18, 3, 9, 9, 12, 9, 27, 12, 21, 9, 27, 27, 36, 12, 36, 21, 33, 4, 12, 12, 16, 12, 36, 16, 28, 7, 21, 21, 28, 11, 33, 18, 29, 3, 9, 9, 12, 9, 27, 12, 21, 9, 27, 27, 36, 12, 36, 21, 33, 9, 27, 27, 36, 27 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS This is the Run Length Transform of S(n) = Lucas(n+1) = 1,3,4,7,11,... (cf. A000204). The Run Length Transform of a sequence {S(n), n>=0} is defined to be the sequence {T(n), n>=0} given by T(n) = Product_i S(i), where i runs through the lengths of runs of 1's in the binary expansion of n. E.g. 19 is 10011 in binary, which has two runs of 1's, of lengths 1 and 2. So T(19) = S(1)*S(2). T(0)=1 (the empty product). LINKS Alois P. Heinz, Table of n, a(n) for n = 0..8191 EXAMPLE From Omar E. Pol, Feb 15 2015: (Start) Written as an irregular triangle in which row lengths are the terms of A011782: 1; 3; 3,4; 3,9,4,7; 3,9,9,12,4,12,7,11; 3,9,9,12,9,27,12,21,4,12,12,16,7,21,11,18; 3,9,9,12,9,27,12,21,9,27,27,36,12,36,21,33,4,12,12,16,12,36,16,28,7,21,21,28,11,33,18,29; ... Right border gives the Lucas numbers (beginning with 1). This is simply a restatement of the theorem that this sequence is the Run Length Transform of A000204. (End) MAPLE A000204 := proc(n) option remember; if n <=2 then 2*n-1; else A000204(n-1)+A000204(n-2); fi; end; ans:=[]; for n from 0 to 100 do lis:=[]; t1:=convert(n, base, 2); L1:=nops(t1); out1:=1; c:=0; for i from 1 to L1 do    if out1 = 1 and t1[i] = 1 then out1:=0; c:=c+1;    elif out1 = 0 and t1[i] = 1 then c:=c+1;    elif out1 = 1 and t1[i] = 0 then c:=c;    elif out1 = 0 and t1[i] = 0 then lis:=[c, op(lis)]; out1:=1; c:=0;    fi;    if i = L1 and c>0 then lis:=[c, op(lis)]; fi;                    od: a:=mul(A000204(i+1), i in lis); ans:=[op(ans), a]; od: ans; CROSSREFS Cf. A245562-A245565, A000204, A001045, A071053. Sequence in context: A027011 A267048 A326401 * A061023 A057690 A318706 Adjacent sequences:  A246008 A246009 A246010 * A246012 A246013 A246014 KEYWORD nonn,base AUTHOR N. J. A. Sloane, Aug 10 2014; revised Sep 05 2014 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 October 17 15:30 EDT 2019. Contains 328116 sequences. (Running on oeis4.)