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A294901 Number of proper divisors of n that are in A257691. 7
0, 1, 1, 2, 1, 3, 1, 2, 2, 3, 1, 3, 1, 3, 3, 2, 1, 3, 1, 3, 3, 3, 1, 3, 2, 3, 2, 3, 1, 4, 1, 2, 3, 3, 3, 3, 1, 3, 3, 3, 1, 4, 1, 3, 3, 3, 1, 3, 2, 4, 3, 3, 1, 3, 3, 3, 3, 3, 1, 4, 1, 3, 3, 2, 3, 4, 1, 3, 3, 4, 1, 3, 1, 3, 4, 3, 3, 4, 1, 3, 2, 3, 1, 4, 3, 3, 3, 3, 1, 4, 3, 3, 3, 3, 3, 3, 1, 3, 3, 4, 1, 4, 1, 3, 4, 3, 1, 3, 1, 4, 3, 3, 1, 4, 3, 3, 3, 3, 3, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..25000

FORMULA

a(n) = Sum_{d|n, d<n} A294905(d).

a(n) = A294903(n) - A294905(n).

a(n) + A294902(n) = A032741(n).

PROG

(PARI)

A292257(n) = sumdiv(n, d, (d<n)*hammingweight(d));

A294905(n) = (A292257(n) <= hammingweight(n));

A294901(n) = sumdiv(n, d, (d<n)*A294905(d));

CROSSREFS

Cf. A000120, A257691, A292257, A294902, A294903, A294904, A294905.

Cf. also A294891.

Sequence in context: A241273 A154263 A293435 * A305818 A303757 A323014

Adjacent sequences:  A294898 A294899 A294900 * A294902 A294903 A294904

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 10 2017

STATUS

approved

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Last modified January 26 20:11 EST 2020. Contains 331288 sequences. (Running on oeis4.)