cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Previous Showing 11-12 of 12 results.

A240942 Numbers k that divide 2^k + 9.

Original entry on oeis.org

1, 11, 121, 323, 117283, 432091, 4132384531, 15516834659, 15941429747, 98953554491, 3272831195051, 7362974489179, 26306805687881, 33869035218491, 280980898827691
Offset: 1

Views

Author

Derek Orr, Aug 04 2014

Keywords

Comments

No other terms below 10^15. Some larger terms: 53496121130110340001650284048539458491, 136243118444105327963550175410279542214992801356720577. - Max Alekseyev, Sep 29 2016

Examples

			2^11 + 9 = 2057 is divisible by 11. Thus 11 is a term of this sequence.
		

Crossrefs

Programs

  • Maple
    select(n -> 9 + 2 &^ n mod n = 0, [$1..10^6]); # Robert Israel, Aug 04 2014
  • PARI
    for(n=1,10^9, if(Mod(2,n)^n==-9, print1(n,", "); ); );

Extensions

a(7)-a(10) from Lars Blomberg, Nov 05 2014
a(11)-a(15) from Max Alekseyev, Sep 29 2016

A334634 Numbers m that divide 2^m + 11.

Original entry on oeis.org

1, 13, 16043199041, 91118493923, 28047837698634913
Offset: 1

Views

Author

Max Alekseyev, Sep 10 2020

Keywords

Comments

Equivalently, numbers m such that 2^m == -11 (mod m).
No other terms below 10^17.

Crossrefs

Solutions to 2^n == k (mod n): A296370 (k=3/2), A187787 (k=1/2), A296369 (k=-1/2), A000079 (k=0), A006521 (k=-1), A015919 (k=2), A006517 (k=-2), A050259 (k=3), A015940 (k=-3), A015921 (k=4), A244673 (k=-4), A128121 (k=5), A245318 (k=-5), A128122 (k=6), A245728 (k=-6), A033981 (k=7), A240941 (k=-7), A015922 (k=8), A245319 (k=-8), A051447 (k=9), A240942 (k=-9), A128123 (k=10), A245594 (k=-10), A033982 (k=11), this sequence (k=-11), A128124 (k=12), A051446 (k=13), A128125 (k=14), A033983 (k=15), A015924 (k=16), A124974 (k=17), A128126 (k=18), A125000 (k=19), A015925 (k=2^5), A015926 (k=2^6), A015927 (k=2^7), A015929 (k=2^8), A015931 (k=2^9), A015932 (k=2^10), A015935 (k=2^11), A015937 (k=2^12).

Extensions

a(5) from Sergey Paramonov, Oct 10 2021
Previous Showing 11-12 of 12 results.