The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A212181

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A212181

Largest odd divisor of tau(n): a(n) = A000265(A000005(n)).
(history; published version)

#44 by Amiram Eldar at Fri Nov 04 05:07:14 EDT 2022

STATUS

reviewed

approved

#43 by Michel Marcus at Fri Nov 04 05:04:54 EDT 2022

STATUS

proposed

reviewed

#42 by Bernard Schott at Fri Nov 04 04:03:04 EDT 2022

STATUS

editing

proposed

#41 by Bernard Schott at Fri Nov 04 04:02:51 EDT 2022

CROSSREFS

Cf. A000005, A000079, A000265, A036537, A108951, A212172, A295664, A331286 (applied to primorial inflation of n).

#40 by Bernard Schott at Fri Nov 04 04:01:39 EDT 2022

COMMENTS

a(n) = 1 iff the number of divisors of n is a power of 2 (A036537). _- _Bernard Schott_, Nov 04 2022

Discussion

Fri Nov 04

04:01

Bernard Schott: Comment iff.

#39 by Bernard Schott at Fri Nov 04 04:00:59 EDT 2022

COMMENTS

a(n) = 1 iff the number of divisors of n is a power of 2 (A036537). Bernard Schott, Nov 04 2022

STATUS

approved

editing

#38 by Michael De Vlieger at Sat Oct 15 08:09:45 EDT 2022

STATUS

reviewed

approved

#37 by Joerg Arndt at Sat Oct 15 05:53:55 EDT 2022

STATUS

proposed

reviewed

#36 by Amiram Eldar at Sat Oct 15 03:59:54 EDT 2022

STATUS

editing

proposed

#35 by Amiram Eldar at Sat Oct 15 03:58:30 EDT 2022

FORMULA

Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = Product_{p odd prime} ((1 - 1/p)*(1 + Sum_{k>=1} a(k+1)/p^k)) = 2.076325817863586... . - ~~~_Amiram Eldar_, Oct 15 2022