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 A295276 a(n) = number of earlier terms (with multiplicity) that have no common one bit with n in binary representation. 2
 0, 1, 1, 3, 1, 4, 1, 7, 2, 6, 2, 8, 3, 5, 1, 15, 6, 9, 3, 13, 4, 8, 3, 18, 7, 9, 3, 13, 3, 6, 1, 31, 11, 16, 6, 22, 7, 12, 4, 29, 13, 12, 5, 17, 5, 9, 2, 41, 15, 23, 8, 23, 7, 13, 4, 31, 12, 14, 5, 16, 4, 7, 1, 63, 24, 36, 16, 31, 12, 20, 8, 45, 20, 24, 12, 22 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS This sequence is a binary variant of A096216: here we check for common one bits and there for common prime factors. LINKS Rémy Sigrist, Table of n, a(n) for n = 1..8192 Rémy Sigrist, Colored scatterplot of the first 2^15 terms (where the color is function of the Hamming weight of n) FORMULA a(n) = #{ k such that 0 < k < n and a(k) AND n = 0 } (where AND stands for the bitwise AND operator). a(2^n) = 2^n-1 for any n > 0. a(2^n-1) = 1 for any n > 1. EXAMPLE The first terms, alongside the earlier terms with no common one bit with n, are:   n   a(n)    Earlier terms with no common one bit with n   --  ----    -------------------------------------------    1     0    ()    2     1    (0)    3     1    (0)    4     3    (0, 1, 1)    5     1    (0)    6     4    (0, 1, 1, 1)    7     1    (0)    8     7    (0, 1, 1, 3, 1, 4, 1)    9     2    (0, 4)   10     6    (0, 1, 1, 1, 4, 1)   11     2    (0, 4)   12     8    (0, 1, 1, 3, 1, 1, 2, 2)   13     3    (0, 2, 2)   14     5    (0, 1, 1, 1, 1)   15     1    (0)   16    15    (0, 1, 1, 3, 1, 4, 1, 7, 2, 6, 2, 8, 3, 5, 1)   17     6    (0, 4, 2, 6, 2, 8)   18     9    (0, 1, 1, 1, 4, 1, 8, 5, 1)   19     3    (0, 4, 8)   20    13    (0, 1, 1, 3, 1, 1, 2, 2, 8, 3, 1, 9, 3) PROG (PARI) a = vector(76); for(n=1, #a, a[n] = sum(i=1, n-1, bitand(a[i], n)==0); print1(a[n] ", ")) CROSSREFS Cf. A096216. Sequence in context: A094119 A210622 A335113 * A301856 A301829 A006022 Adjacent sequences:  A295273 A295274 A295275 * A295277 A295278 A295279 KEYWORD nonn,base AUTHOR Rémy Sigrist, Nov 19 2017 STATUS approved

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Last modified September 17 19:58 EDT 2021. Contains 347489 sequences. (Running on oeis4.)