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.

A061155 Numbers k such that k*2^m+1 is prime for exactly one exponent m in the range 0<=m<=k.

Original entry on oeis.org

31, 91, 353, 493, 512, 587, 692, 752, 829, 919, 1021, 1024, 1174, 1384, 1643, 1658, 1669, 1735, 1838, 1913, 1921, 2042, 2048, 2057, 2311, 2423, 2768, 3167, 3286, 3316, 3443, 3826, 3829, 3842, 3983, 4037, 4084, 4096, 4114, 4429, 4801, 4846, 4861, 5536, 6319, 6334, 6529
Offset: 1

Views

Author

Patrick De Geest, Apr 15 2001

Keywords

Comments

Corresponding exponent values see A061156.

Links

Crossrefs

Cf. A061153, A061154, A061156, A061157, A061158.

Extensions

Offset corrected and a(29)-a(43) from Sean A. Irvine, Jan 24 2023
a(44) and beyond from Michael S. Branicky, Jan 25 2023

A061156 Exponent values m resulting from A061155.

Original entry on oeis.org

8, 8, 21, 2, 7, 227, 11, 579, 18, 2, 112, 6, 226, 10, 1465, 17, 230, 88, 1, 9, 24, 111, 5, 295, 76, 881, 9, 83, 1464, 16, 3137, 8, 1230, 23, 389, 3, 110, 4, 294, 342, 752, 880, 2492, 8, 4606, 82, 10, 1463, 15, 279, 3136, 3, 964, 1839, 135, 7, 1229, 2174, 388, 88, 109
Offset: 1

Views

Author

Patrick De Geest, Apr 15 2001

Keywords

Links

Crossrefs

Cf. A061153, A061154, A061155, A061157, A061158.

Extensions

Offset corrected and a(29)-a(44) from Sean A. Irvine, Jan 24 2023
a(45) and beyond from Michael S. Branicky, Jan 25 2023

A061153 Numbers k such that k*2^m+1 are composites for all exponents m in the range 0<=m<=k.

Original entry on oeis.org

47, 94, 188, 257, 376, 383, 766, 881, 1532, 2897, 3061, 3064, 4847, 5297, 5359, 5794, 5897, 6122, 6128, 7013, 7651, 8423, 9694, 10223, 10594, 10718, 11794, 12244, 13787, 14026, 14027, 15302, 16817, 16846, 18107, 19249, 19388, 20446, 21181, 21188
Offset: 1

Views

Author

Patrick De Geest, Apr 15 2001

Keywords

Crossrefs

Cf. A061154, A061155, A061156, A061157, A061158.

Programs

  • Maple
    filter:= n -> andmap(not isprime, [seq(n*2^m+1,m=0..n)]):
select(filter, [$1..10000]); # Robert Israel, Sep 22 2019

Extensions

More terms from Robert Israel, Sep 22 2019
Offset corrected by Sean A. Irvine, Jan 22 2023

A061154 Numbers k such that k*2^m-1 are composites for all exponents m in the range 0<=m<=k.

Original entry on oeis.org

148, 191, 296, 592, 659, 1103, 1184, 1211, 1318, 1348, 2206, 2293, 2368, 2422, 2636, 2696, 3817, 4207, 4586, 4844, 5272, 5392, 7634, 9172, 9221, 9688, 10391, 10451, 10544, 10784, 11519, 14347, 14459, 15268, 16829, 18344, 18442, 19376, 20782, 21088, 23038, 23669
Offset: 1

Views

Author

Patrick De Geest, Apr 15 2001

Keywords

Crossrefs

Cf. A061153, A061155, A061156, A061157, A061158.

Extensions

Offset corrected and a(19)-a(26) from Sean A. Irvine, Jan 24 2023
a(27)-a(42) from Michael S. Branicky, Jan 26 2023
Showing 1-4 of 4 results.

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

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