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 1-5 of 5 results.

A127559 Decimal expansion of the number 734.000353982279850297391846... having continued fraction expansion 734, 2825, 5957, 10305, 13932, ... (interprimes of third order A126556).

Original entry on oeis.org

7, 3, 4, 0, 0, 0, 3, 5, 3, 9, 8, 2, 2, 7, 9, 8, 5, 0, 2, 9, 7, 3, 9, 1, 8, 4, 6, 1, 5, 9, 2, 7, 6, 9, 4, 9, 1, 1, 2, 4, 7, 3, 4, 1, 2, 2, 3, 9, 9, 1, 6, 1, 1, 5, 8, 1, 5, 8, 2, 6, 1, 8, 9, 2, 4, 0, 3, 1, 3, 6, 2, 0, 9, 5, 9, 1, 6, 3, 9, 3, 0, 9, 5, 9, 1, 7, 9, 4, 0, 9, 5, 2, 7, 0, 5, 4, 2, 8, 2, 5
Offset: 3

Views

Author

Artur Jasinski, Jan 18 2007

Keywords

Crossrefs

Extensions

Offset corrected by R. J. Mathar, Feb 05 2009

A126557 Primes in A126556.

Original entry on oeis.org

174737, 224327, 433813, 541447, 787243, 969667, 980081, 1080787, 1286581, 1372979, 1534513, 1567037, 1570649, 1577189, 1659673, 1726993, 1931291, 2242883, 2282041, 2415557, 2460827, 3162503, 3711047, 4090787, 4450373
Offset: 1

Views

Author

Artur Jasinski, Dec 27 2006

Keywords

Comments

Prime interprimes of third order.
Primes that are the arithmetic mean of two consecutive prime interprimes of second order; primes of the form (A126555(k)+A126555(k+1))/2.

Crossrefs

Cf. A006562 (balanced primes), A024675 (interprimes), A126554 (interprimes of second order), A126555 (prime interprimes of second order), A126556 (interprimes of third order).

Programs

  • PARI
    {m=5000000;a=0;g=0;p=2;q=3;r=5;while(r<=m,if((p+r)/2==q,if(a>0,b=(a+q)/2;if(isprime(b),if(g>0,if(isprime(h=(g+b)/2),print1(h,",")));g=b));a=q);p=q;q=r; r=nextprime(r+1))} \\ Klaus Brockhaus, Jan 11 2007

Extensions

Edited and extended by Klaus Brockhaus, Jan 11 2007

A126558 Arithmetic mean of two consecutive prime interprimes of third order: interprimes of fourth order.

Original entry on oeis.org

199532, 329070, 487630, 664345, 878455, 974874, 1030434, 1183684, 1329780, 1453746, 1550775, 1568843, 1573919, 1618431, 1693333, 1829142, 2087087, 2262462, 2348799, 2438192, 2811665, 3436775, 3900917, 4270580, 4830665
Offset: 1

Views

Author

Artur Jasinski, Dec 27 2006

Keywords

Comments

For primes in this sequence (prime interprimes of fourth order) see A127364.

Crossrefs

Cf. A006562 (balanced primes), A024675 (interprimes), A126554 (interprimes of second order), A126555 (prime interprimes of second order), A126556 (interprimes of third order), A126557 (prime interprimes of third order).

Programs

  • PARI
    {m=5000000;a=0;g=0;e=0;p=2;q=3;r=5;while(r<=m,if((p+r)/2==q,if(a>0,b=(a+q)/2;if(isprime(b),if(g>0,h=(g+b)/2;if(isprime(h),if(e>0,f=(e+h)/2;print1(f,","));e=h));g=b));a=q);p=q;q=r;r=nextprime(r+1))} \\ Klaus Brockhaus, Jan 11 2007

Formula

a(n) = (A126557(n)+A126557(n+1))/2.

Extensions

Edited and extended by Klaus Brockhaus, Jan 11 2007

A127364 Primes in A126558.

Original entry on oeis.org

1693333, 14251277, 17306687, 18067739, 25852399, 29126567, 55781581, 62333321, 113347009, 173863769, 204308891, 211281809, 247612801, 256102939, 267030149, 267670129, 277108457, 291010691, 298502489, 337176617, 365570923, 370598051
Offset: 1

Views

Author

Klaus Brockhaus, Jan 11 2007

Keywords

Comments

Prime interprimes of fourth order.
Primes that are the arithmetic mean of two consecutive prime interprimes of third order; primes of the form (A126557(k)+A126557(k+1))/2.

Crossrefs

Cf. A006562 (balanced primes), A024675 (interprimes), A126554 (interprimes of second order), A126555 (prime interprimes of second order), A126556 (interprimes of third order), A126557 (prime interprimes of third order), A126558 (interprimes of fourth order).

Programs

  • PARI
    {m=400000000;a=0;g=0;e=0;p=2;q=3;r=5;while(r<=m,if((p+r)/2==q,if(a>0,b=(a+q)/2;if(isprime(b),if(g>0,h=(g+b)/2;if(isprime(h),if(e>0,f=(e+h)/2;if(isprime(f),print1(f,",")));e=h));g=b));a=q);p=q;q=r;r=nextprime(r+1))}

A126559 Least interprime of n-th order.

Original entry on oeis.org

4, 29, 734, 199532, 7972305, 731908877
Offset: 1

Views

Author

Artur Jasinski, Dec 27 2006

Keywords

Examples

			A024675(1) = 4, A126554(1) = 29, A126556(1) = 734, A126558(1) = 199532.
		

Crossrefs

Cf. A006562 (balanced primes), A024675 (interprimes), A126554 (interprimes of second order), A126556 (interprimes of third order), A126558 (interprimes of fourth order).

Extensions

Edited by Klaus Brockhaus, Jan 11 2007
a(5)-a(6) from Amiram Eldar, Mar 28 2020
Showing 1-5 of 5 results.