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A283988 a(n) = A002487(n-1) AND A002487(n), where AND is bitwise-and (A004198). 7
0, 1, 0, 0, 1, 2, 2, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 4, 4, 3, 0, 0, 5, 2, 2, 5, 0, 0, 3, 4, 4, 1, 0, 4, 1, 0, 0, 3, 2, 2, 3, 8, 8, 5, 4, 4, 1, 0, 0, 1, 4, 4, 5, 8, 8, 3, 2, 2, 3, 0, 0, 1, 4, 0, 1, 6, 2, 1, 4, 8, 9, 4, 4, 11, 2, 2, 1, 0, 8, 1, 2, 10, 3, 0, 0, 5, 0, 0, 1, 0, 0, 3, 0, 0, 9, 2, 2, 9, 0, 0, 3, 0, 0, 1, 0, 0, 5, 0, 0, 3, 10, 2, 1, 8, 0, 1, 2, 2, 11, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

Index entries for sequences related to binary expansion of n

FORMULA

a(n) = A002487(n-1) AND A002487(n), where AND is bitwise-and (A004198).

a(n) = A283986(n) - A283987(n).

a(n) = A007306(n) - A283986(n) = (A007306(n) - A283987(n))/2.

a(n) = A283978((2*n)-1).

MATHEMATICA

a[0] = 0; a[1] = 1; a[n_] := If[EvenQ@ n, a[n/2], a[(n - 1)/2] + a[(n + 1)/2]]; Table[BitAnd[a[n - 1], a@ n], {n, 120}] (* Michael De Vlieger, Mar 22 2017 *)

PROG

(Scheme) (define (A283988 n) (A004198bi (A002487 (- n 1)) (A002487 n)))  ;; Where A004198bi implements bitwise-AND (A004198).

(PARI) A(n) = if(n<2, n, if(n%2, A(n\2) + A((n + 1)/2), A(n/2)));

for(n=1, 120, print1(bitand(A(n - 1), A(n)), ", ")) \\ Indranil Ghosh, Mar 23 2017

CROSSREFS

Odd bisection of A283978.

Cf. A002487, A004198, A007306, A283986, A283987.

Cf. A283973 (positions of zeros), A283974 (nonzeros).

Sequence in context: A049783 A287320 A210502 * A276204 A347883 A024712

Adjacent sequences:  A283985 A283986 A283987 * A283989 A283990 A283991

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Mar 21 2017

STATUS

approved

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Last modified December 4 08:57 EST 2021. Contains 349484 sequences. (Running on oeis4.)