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.

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A067375 Integers expressible as the sum of (at least two) consecutive primes in at least 5 ways.

Original entry on oeis.org

16277, 20272, 25416, 28500, 34421, 41074, 45101, 46660, 50560, 53424, 59068, 68787, 70104, 70692, 71548, 78756, 85433, 85481, 88453, 94350, 98881, 105827, 117907, 120151, 121847, 125952, 130638, 130789, 131420, 132539, 133367, 134376, 135918, 139853, 158810
Offset: 1

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Author

Patrick De Geest, Feb 04 2002

Keywords

Examples

			E.g. 16277 = (#7,2297) (#11,1451) (#13,1213) (#35,359) (#37,331).
		

Crossrefs

Programs

  • Mathematica
    t={};Do[p=Prime[m];Do[p=p+Prime[n];If[p<200000,AppendTo[t,p]],{n,m+1,7001}],{m,1,7000}];t=Sort@t;f5[l_]:=Module[{t={}},Do[If[l[[n]]==l[[n+4]],AppendTo[t,l[[n]]]],{n,Length[l]-4}];t];Union@f5[t] (* Vladimir Joseph Stephan Orlovsky, Jan 30 2012 *)

Formula

A084143(a(n)) > 4. - Ray Chandler, Sep 20 2023

Extensions

Offset and a(35) corrected by Donovan Johnson, Nov 14 2013

A067376 Smallest integer expressible as the sum of (at least two) consecutive primes in n ways.

Original entry on oeis.org

5, 36, 240, 311, 16277, 130638, 218918, 9186778, 274452156, 4611108324, 12941709050
Offset: 1

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Author

Patrick De Geest, Feb 04 2002

Keywords

Comments

a(10)-a(11) found by Wilfred Whiteside in 2007 (see Rivera link). - Michael S. Branicky, Jul 27 2022

Examples

			In n=7 ways: 218918 = (#12,18199) (#16,13619) (#22,9851) (#28,7691) (#38,5623) (#46,4561) (#62,3301).
		

Crossrefs

Extensions

Offset corrected and a(8)-a(9) from Donovan Johnson, Mar 14 2010
a(10) confirmed and a(10)-a(11) entered by Michael S. Branicky, Jul 27 2022

A350334 Primes expressible as the sum of (at least two) consecutive primes in at least 6 ways.

Original entry on oeis.org

442019, 1866373, 3051161, 3634531, 3704819, 3839677, 3890609, 4539331, 4711937, 5011213, 5069023, 5369743, 5384221, 6137587, 6783263, 6893273, 9213073, 10354177, 10602763, 11394193, 11849339, 12012257, 13126801, 13322887, 14385781, 15077143, 17225003, 19301221
Offset: 1

Views

Author

Jon E. Schoenfield, Dec 25 2021

Keywords

Comments

Subsequence of A164556.

Examples

			442019 is a term because it is a prime and
   442019 = Sum_{j=13620..13622} prime(j)
          = Sum_{j=5044..5052} prime(j)
          = Sum_{j=2019..2043} prime(j)
          = Sum_{j=1573..1605} prime(j)
          = Sum_{j=954..1010} prime(j)
          = Sum_{j=81..381} prime(j).
		

Crossrefs

A350335 Primes expressible as the sum of (at least two) consecutive primes in at least 7 ways.

Original entry on oeis.org

3634531, 27411611, 28127521, 28445689, 48205429, 54604973, 56857523, 63461429, 70734089, 72087167, 75489781, 82183951, 83020733, 89752433, 92712023, 94026311, 100925263, 111282419, 137392361, 163506407, 164711999, 194039771, 195327179, 196364899, 196876789
Offset: 1

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Author

Jon E. Schoenfield, Dec 25 2021

Keywords

Comments

Subsequence of A350334.

Examples

			3634531 is a term because it is a prime and
   3634531 = Sum_{j=42997..43003} prime(j)
           = Sum_{j=15749..15769} prime(j)
           = Sum_{j=7294..7342} prime(j)
           = Sum_{j=7032..7082} prime(j)
           = Sum_{j=3397..3509} prime(j)
           = Sum_{j=165..1003} prime(j)
           = Sum_{j=65..995} prime(j).
		

Crossrefs

A372507 a(n) is the smallest number k such that prime(k) is expressible as the sum of (at least two) consecutive primes in n ways.

Original entry on oeis.org

3, 13, 64, 64, 3677, 37096, 259073, 2899722, 88790445, 1554106234, 6711446232, 215580239668
Offset: 1

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Author

Ilya Gutkovskiy, May 04 2024

Keywords

Crossrefs

Formula

a(n) = A000720(A067381(n)).
Previous Showing 11-15 of 15 results.