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.

A086498 Rearrangement of primes such that every (2n)-th partial sum is a prime. Every (2n+1)-st term is the smallest prime which has not been included earlier.

Original entry on oeis.org

2, 3, 5, 7, 11, 13, 17, 31, 19, 23, 29, 37, 41, 43, 47, 61, 53, 67, 59, 73, 71, 97, 79, 83, 89, 103, 101, 109, 107, 127, 113, 151, 131, 139, 137, 163, 149, 199, 157, 173, 167, 181, 179, 271, 191, 229, 193, 257, 197, 277, 211, 239, 223, 263, 227, 313, 233, 241, 251
Offset: 1

Views

Author

Amarnath Murthy, Jul 28 2003

Keywords

Crossrefs

Programs

  • Maple
    N:= 100: # to get all terms before the first term > Prime(N).
    Primes:= [seq(ithprime(i),i=2..N)]: nP:= N-1: S:= 2: R:= 2:
    do
      found:= false;
      for j from 1 to nP do
        if isprime(S+Primes[j]) then
          R:= R, Primes[j];
          S:= S + Primes[j];
          Primes:= subsop(j=NULL, Primes);
          nP:= nP-1;
          found:= true;
          break
        fi
      od;
      if not found or nP = 0 then break fi;
      R:= R, Primes[1];
      S:= S + Primes[1];
      Primes:= Primes[2..-1];
      nP:= nP-1;
    od:
    R; # Robert Israel, Aug 04 2020

Extensions

More terms from Ray Chandler, Sep 17 2003

A086496 Rearrangement of natural numbers such that every 2n-th partial sum is prime. Every (2n+1)-th term is the smallest number not included earlier.

Original entry on oeis.org

1, 2, 3, 5, 4, 8, 6, 12, 7, 11, 9, 15, 10, 14, 13, 17, 16, 20, 18, 32, 19, 21, 22, 26, 23, 25, 24, 36, 27, 33, 28, 34, 29, 31, 30, 42, 35, 43, 37, 39, 38, 46, 40, 58, 41, 47, 44, 52, 45, 51, 48, 62, 49, 63, 50, 60, 53, 59, 54, 74, 55, 57, 56, 70, 61, 77, 64, 76, 65, 79, 66, 72
Offset: 1

Views

Author

Amarnath Murthy, Jul 28 2003

Keywords

Examples

			1+2, 1+2+3+5, etc. yield primes.
		

Crossrefs

Extensions

More terms from Ray Chandler, Sep 16 2003

A086499 Primes arising in A086498: a(n) = (2n)-th partial sum of A086498.

Original entry on oeis.org

5, 17, 41, 89, 131, 197, 281, 389, 509, 641, 809, 971, 1163, 1373, 1607, 1871, 2141, 2441, 2789, 3119, 3467, 3917, 4337, 4787, 5261, 5711, 6197, 6737, 7211, 7793, 8369, 8933, 9623, 10271, 10937, 11657, 12377, 13259, 14057, 14879, 15731, 16553, 17393
Offset: 1

Views

Author

Amarnath Murthy, Jul 28 2003

Keywords

Crossrefs

Extensions

More terms from Ray Chandler, Sep 17 2003
Showing 1-3 of 3 results.