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.

Showing 1-4 of 4 results.

A061410 Numbers k such that m*2^k+1 is not prime for all coefficients m in the range 0<=m<=k.

Original entry on oeis.org

9, 10, 22, 31, 86, 99, 100, 101, 113, 114, 115, 130, 135, 136, 149, 154, 169, 217, 218, 223, 224, 283, 301, 309, 358, 383, 384, 422, 423, 424, 425, 426, 449, 457, 473, 495, 505, 506, 541, 542, 548, 549, 564, 571, 572, 573, 628, 668, 670, 681, 682, 683, 713
Offset: 1

Views

Author

Patrick De Geest, May 15 2001

Keywords

Links

Crossrefs

Cf. A061411, A061412, A061413, A061414, A061415.

Programs

  • Maple
    filter:= n -> andmap(not isprime, [seq(m*2^n+1,m=1..n)]):
select(filter, [$1..1000]); # Robert Israel, Dec 10 2017
  • Mathematica
    okQ[n_] := AllTrue[2^n Range[n] + 1, CompositeQ];
Select[Range[1000], okQ] (* Jean-François Alcover, Mar 25 2019 *)
  • PARI
    isok(n) = {for (m=0, n, if (isprime(m*2^n+1), return (0));); return (1);} \\ Michel Marcus, Dec 11 2017

A061414 Numbers k such that m*2^k - 1 is prime for exactly one coefficient m in the range 0 <= m <= k.

Original entry on oeis.org

8, 9, 19, 23, 25, 26, 34, 39, 58, 64, 66, 68, 82, 83, 84, 86, 108, 109, 117, 118, 128, 129, 130, 134, 136, 150, 151, 175, 176, 178, 179, 194, 197, 227, 231, 234, 240, 241, 248, 258, 259, 275, 276, 278, 281, 309, 315, 316, 317, 330, 331, 332, 336, 337, 339, 340
Offset: 1

Views

Author

Patrick De Geest, May 15 2001

Keywords

Comments

For corresponding coefficient values see A061415.

Crossrefs

Cf. A061410, A061411, A061412, A061413, A061415.

Extensions

Name edited and offset changed by Jon E. Schoenfield, Oct 26 2019

A061411 Numbers k such that m*2^k - 1 is nonprime for all coefficients m in the range 0 <= m <= k.

Original entry on oeis.org

1, 22, 24, 65, 110, 112, 135, 137, 166, 167, 218, 219, 220, 228, 229, 239, 257, 280, 310, 344, 345, 346, 398, 399, 403, 404, 405, 430, 439, 440, 475, 494, 504, 505, 508, 522, 524, 534, 535, 536, 557, 559, 592, 619, 620, 624, 625, 626, 679, 703, 705, 706
Offset: 1

Views

Author

Patrick De Geest, May 15 2001

Keywords

Crossrefs

Cf. A061410, A061412, A061413, A061414, A061415.

Extensions

Name edited and Offset changed by Jon E. Schoenfield, Oct 26 2019

A061412 Numbers k such that m*2^k + 1 is prime for exactly one coefficient m in the range 0 <= m <= k.

Original entry on oeis.org

1, 2, 3, 4, 5, 18, 21, 23, 24, 26, 30, 32, 34, 35, 56, 57, 58, 59, 69, 70, 71, 87, 95, 96, 97, 106, 107, 108, 109, 112, 116, 120, 121, 131, 137, 139, 140, 142, 150, 151, 156, 159, 161, 163, 171, 172, 176, 177, 178, 181, 191, 192, 194, 195, 196, 197, 212, 219, 220
Offset: 1

Views

Author

Patrick De Geest, May 15 2001

Keywords

Comments

For corresponding coefficient values see A061413.

Crossrefs

Cf. A061410, A061411, A061413, A061414, A061415.

Extensions

Name edited and Offset changed by Jon E. Schoenfield, Oct 26 2019
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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