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A368314
a(n) is the number of numbers that can be obtained by replacing any positive number without leading zeros, say m, appearing in the binary expansion of n by one of the divisors of m.
4
1, 2, 2, 3, 3, 4, 3, 4, 4, 5, 5, 6, 5, 6, 5, 5, 5, 7, 6, 7, 7, 8, 7, 8, 7, 8, 8, 9, 7, 10, 7, 6, 7, 7, 8, 10, 9, 9, 9, 9, 8, 12, 10, 11, 11, 11, 10, 10, 9, 12, 10, 11, 10, 13, 12, 12, 11, 11, 10, 15, 11, 13, 11, 7, 8, 11, 9, 9, 10, 13, 10, 13, 11, 12, 14, 12
OFFSET
1,2
COMMENTS
a(n) gives the number of terms in the n-th row of A368313.
FORMULA
a(n) >= A000005(n).
a(2^k) = k + 1 for any k >= 0.
EXAMPLE
For n = 42: the 42nd row of A368313 contains 12 terms (1, 2, 3, 5, 6, 7, 10, 14, 21, 22, 26, 42), so a(42) = 12.
PROG
(PARI) See Links section.
CROSSREFS
Cf. A000005, A368195 (decimal variant), A368313.
Sequence in context: A161511 A319856 A100197 * A356874 A057022 A287896
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Dec 21 2023
STATUS
approved