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 A135416 a(n) = A036987(n)*(n+1)/2. 31
 1, 0, 2, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Guy Steele defines a family of 36 integer sequences, denoted here by GS(i,j) for 1 <= i, j <= 6, as follows. a[1]=1; a[2n] = i-th term of {0,1,a[n],a[n]+1,2a[n],2a[n]+1}; a[2n+1] = j-th term of {0,1,a[n],a[n]+1,2a[n],2a[n]+1}. The present sequence is GS(1,5). The full list of 36 sequences: GS(1,1) = A000007 GS(1,2) = A000035 GS(1,3) = A036987 GS(1,4) = A007814 GS(1,5) = A135416 (the present sequence) GS(1,6) = A135481 GS(2,1) = A135528 GS(2,2) = A000012 GS(2,3) = A000012 GS(2,4) = A091090 GS(2,5) = A135517 GS(2,6) = A135521 GS(3,1) = A036987 GS(3,2) = A000012 GS(3,3) = A000012 GS(3,4) = A000120 GS(3,5) = A048896 GS(3,6) = A038573 GS(4,1) = A135523 GS(4,2) = A001511 GS(4,3) = A008687 GS(4,4) = A070939 GS(4,5) = A135529 GS(4,6) = A135533 GS(5,1) = A048298 GS(5,2) = A006519 GS(5,3) = A080100 GS(5,4) = A087808 GS(5,5) = A053644 GS(5,6) = A000027 GS(6,1) = A135534 GS(6,2) = A038712 GS(6,3) = A135540 GS(6,4) = A135542 GS(6,5) = A054429 GS(6,6) = A003817 (with a(0)=1): Moebius transform of A038712. LINKS Antti Karttunen, Table of n, a(n) for n = 1..65537 FORMULA G.f.: sum{k>=1, 2^(k-1)*x^(2^k-1) }. Recurrence: a(2n+1) = 2a(n), a(2n) = 0, starting a(1) = 1. MAPLE GS:=proc(i, j, M) local a, n; a:=array(1..2*M+1); a[1]:=1; for n from 1 to M do a[2*n] :=[0, 1, a[n], a[n]+1, 2*a[n], 2*a[n]+1][i]; a[2*n+1]:=[0, 1, a[n], a[n]+1, 2*a[n], 2*a[n]+1][j]; od: a:=convert(a, list); RETURN(a); end; GS(1, 5, 200): MATHEMATICA i = 1; j = 5; Clear[a]; a[1] = 1; a[n_?EvenQ] := a[n] = {0, 1, a[n/2], a[n/2]+1, 2*a[n/2], 2*a[n/2]+1}[[i]]; a[n_?OddQ] := a[n] = {0, 1, a[(n-1)/2], a[(n-1)/2]+1, 2*a[(n-1)/2], 2*a[(n-1)/2]+1}[[j]]; Array[a, 105] (* Jean-François Alcover, Sep 12 2013 *) PROG (PARI) A048298(n) = if(!n, 0, if(!bitand(n, n-1), n, 0)); A135416(n) = (A048298(n+1)/2); \\ Antti Karttunen, Jul 22 2018 CROSSREFS Equals A048298(n+1)/2. Cf. A036987, A182660. Sequence in context: A245527 A287871 A336644 * A134309 A051516 A236799 Adjacent sequences:  A135413 A135414 A135415 * A135417 A135418 A135419 KEYWORD nonn AUTHOR N. J. A. Sloane, based on a message from Guy Steele and Don Knuth, Mar 01 2008 EXTENSIONS Formulae and comments by Ralf Stephan, Jun 20 2014 STATUS approved

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Last modified April 20 06:59 EDT 2021. Contains 343125 sequences. (Running on oeis4.)