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A282843 Numbers n for which id(n) = id(n + id(n)), where id(n) = A037445(n) is the number of infinitary divisors of n. 1
2, 3, 5, 6, 7, 8, 9, 10, 11, 14, 17, 18, 22, 23, 28, 29, 32, 34, 35, 41, 44, 46, 47, 48, 51, 58, 59, 64, 65, 70, 71, 76, 79, 81, 82, 87, 88, 91, 94, 95, 96, 101, 102, 107, 111, 112, 115, 118, 119, 125, 128, 129, 130, 132, 137, 141, 142, 143, 144, 149, 152, 155 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The infinitary analog of A175304. The sequence contains smaller of pairs(p,q) of terms of A050376 if q-p=2 (Fermi-Dirac twin primes). Unlike A175304, this sequence contains some squares (64,81,144,...).

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

PROG

(PARI) id(n)=2^vecsum(apply(hammingweight, factor(n)[, 2]))

is(n)=my(i=id(n)); id(n+i)==i \\ Charles R Greathouse IV, Feb 22 2017

CROSSREFS

Cf. A037445, A050376, A175304.

Sequence in context: A137407 A261406 A264387 * A074137 A206027 A039222

Adjacent sequences:  A282840 A282841 A282842 * A282844 A282845 A282846

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Feb 22 2017

EXTENSIONS

More term from Peter J. C. Moses, Feb 22 2017

STATUS

approved

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Last modified September 20 07:59 EDT 2019. Contains 327214 sequences. (Running on oeis4.)