A324658 a(n) = n - A324659(n), where A324659(n) is half of bitwise-AND of 2*n and sigma(n).

1, 2, 1, 4, 4, 0, 3, 8, 9, 2, 9, 0, 8, 2, 3, 16, 16, 0, 17, 0, 5, 4, 19, 0, 16, 10, 11, 0, 16, 26, 15, 32, 33, 32, 35, 0, 36, 32, 35, 0, 40, 10, 41, 4, 8, 10, 39, 0, 33, 16, 19, 4, 36, 2, 19, 0, 17, 18, 33, 40, 32, 14, 11, 64, 65, 2, 65, 64, 69, 6, 67, 8, 72, 66, 65, 8, 77, 10, 71, 0, 65, 64, 81, 4, 65, 20, 67, 0, 80

Offset

1,2

Links

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

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Index entries for sequences related to binary expansion of n

Index entries for sequences related to sigma(n)

Formula

a(n) = n - A324659(n) = n - A318468(n)/2 = n - ((2*n AND sigma(n))/2).

Mathematica

Array[# - BitAnd[2*#, DivisorSigma[1, #]]/2 &, 100] (* Paolo Xausa, Mar 13 2024 *)

Prog

(PARI) A324658(n) = (n-(bitand(2*n, sigma(n))/2));

Crossrefs

Cf. A000203, A004198, A318468, A324648, A324659.

Cf. A324652 (positions of zeros).

Sequence in context: A036069 A338846 A009477 * A105568 A335830 A004175

Adjacent sequences: A324655 A324656 A324657 * A324659 A324660 A324661

Keyword

nonn,look

Author

Antti Karttunen, Mar 14 2019

Status

approved