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 1-3 of 3 results.

A138755 Primes p2 such that p1^3 + p2^2 is an average of twin primes and p1 < p2 are consecutive primes.

Original entry on oeis.org

29, 2081, 2357, 3373, 3727, 4013, 4093, 5233, 6007, 7829, 15559, 15797, 16319, 17123, 18523, 20143, 22037, 23071, 25261, 26293, 28019, 28289, 33797, 39499, 41627, 42181, 42929, 45121, 48533, 48823, 49123, 50417, 52697, 54629, 57973, 58897, 60887, 62761, 64381
Offset: 1

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Examples

			29 is a term since 23 and 29 are consecutive primes, 23^3 + 29^2 = 13008, and (13007, 13009) are twin primes.
		

Crossrefs

Programs

  • Magma
    [NthPrime(k+1):k in [1..7000]| IsPrime(q-1) and IsPrime(q+1) where q is NthPrime(k)^3+ NthPrime(k+1)^2]; // Marius A. Burtea, Dec 22 2019
  • Mathematica
    a={};Do[p1=Prime[n];p2=Prime[n+1];pp=p1^3+p2^2;If[PrimeQ[pp-1]&&PrimeQ[pp+1],AppendTo[a,p2]],{n,16^3}];Print[a];
    Select[Partition[Prime[Range[6500]],2,1],AllTrue[#[[1]]^3+#[[2]]^2+{1,-1},PrimeQ]&][[All,2]] (* Harvey P. Dale, Aug 29 2021 *)

Extensions

More terms from Amiram Eldar, Dec 22 2019

A138716 Primes p2 such that p1^2 + p2^3 is an average of twin primes and p1 < p2 are consecutive primes.

Original entry on oeis.org

29, 107, 1481, 1613, 2393, 2879, 4421, 5021, 5519, 5573, 6269, 7817, 8447, 9629, 11489, 11981, 12011, 17159, 17573, 18461, 19961, 21713, 23021, 23291, 23747, 24917, 26339, 27947, 29021, 29201, 29663, 30893, 32063, 32717, 34217, 34589, 35159, 36527, 36899, 44753
Offset: 1

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Author

Keywords

Examples

			29 is a term since 23 and 29 are consecutive primes, 23^2 + 29^3 = 24918, and (24917, 24919) are twin primes.
		

Crossrefs

Programs

  • Magma
    [NthPrime(k+1):k in [1..5000]| IsPrime(q-1) and IsPrime(q+1) where q is NthPrime(k)^2+ NthPrime(k+1)^3]; // Marius A. Burtea, Dec 22 2019
  • Mathematica
    a={};Do[p1=Prime[n];p2=Prime[n+1];pp=p1^2+p2^3;If[PrimeQ[pp-1]&&PrimeQ[pp+1],AppendTo[a,p2]],{n,16^3}];Print[a];
    Select[Partition[Prime[Range[5000]],2,1],AllTrue[#[[1]]^2+#[[2]]^3+{1,-1},PrimeQ]&] [[All,2]] (* Harvey P. Dale, Oct 29 2022 *)

Extensions

More terms from Amiram Eldar, Dec 22 2019

A139777 Average of twin primes p4 = p1^3 + p2^2 such that p1 < p2 are consecutive primes and p3 = p1^2 + p2^3 is also an average of twin primes.

Original entry on oeis.org

13008, 9268057799643918, 1151303780719281840798, 1166398496059056623580, 1408815704665167877050, 1611023943160530038112, 1839284737645145603808, 1876391173984974899670, 2541672151459722294708, 3760269231809150191932, 13232137801909374644760, 19086525662779517405622
Offset: 1

Views

Author

Keywords

Examples

			13008 = 23^3 + 29^2 is a term since 23 and 29 are consecutive primes, (13007, 13009) are twin primes, 23^2 + 29^3 = 24918, and (24917, 24919) are also twin primes.
		

Crossrefs

Programs

  • Mathematica
    a={};Do[p1=Prime[n];p2=Prime[n+1];p3=p1^2+p2^3;p4=p1^3+p2^2;If[PrimeQ[p3-1]&&PrimeQ[p3+1]&&PrimeQ[p4-1]&&PrimeQ[p4+1],AppendTo[a,p4]],{n,13^5}];Print[a];

Extensions

More terms from Amiram Eldar, Dec 22 2019
Showing 1-3 of 3 results.