login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A293275 Exponent of highest power of 2 dividing the n-th (2,k)-perfect number A019278. 1
0, 1, 2, 3, 0, 4, 0, 3, 1, 2, 6, 2, 5, 3, 4, 4, 5, 3, 9, 6, 0, 6, 9, 2, 12, 9, 9, 4, 0, 9, 5, 8, 5, 1, 12, 6, 16, 12, 2, 7, 18, 8, 3, 4, 0, 10, 8, 5, 16, 2, 8, 16, 14, 10, 6, 1, 2, 8, 3, 18, 12, 8, 18, 11, 11, 4, 14, 9, 5, 10, 6, 11, 5, 5, 16, 7, 14, 12, 8, 13, 9, 18 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Michel Marcus, Table of n, a(n) for n = 1..130

FORMULA

a(n) = A007814(A019278(n)).

PROG

(PARI) lista(nn) = for (n=1, nn, if (denominator(sigma(sigma(n))/n) == 1, print1(valuation(n, 2), ", ")); ); \\ Michel Marcus, Oct 10 2017

CROSSREFS

Cf. A007814, A019278, A205597 (when a(n) is zero).

Cf. A134665 (analog for multiperfect numbers).

Sequence in context: A324906 A164917 A166238 * A014197 A181308 A292246

Adjacent sequences:  A293272 A293273 A293274 * A293276 A293277 A293278

KEYWORD

nonn

AUTHOR

Michel Marcus, Oct 10 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 9 16:50 EDT 2020. Contains 335545 sequences. (Running on oeis4.)