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 1-2 of 2 results.

A270999 Table read by rows: list of prime 5-tuples of the form (p, p+4, p+6, p+10, p+12).

Original entry on oeis.org

7, 11, 13, 17, 19, 97, 101, 103, 107, 109, 1867, 1871, 1873, 1877, 1879, 3457, 3461, 3463, 3467, 3469, 5647, 5651, 5653, 5657, 5659, 15727, 15731, 15733, 15737, 15739, 16057, 16061, 16063, 16067, 16069, 19417, 19421, 19423, 19427, 19429, 43777, 43781, 43783, 43787, 43789
Offset: 1

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Author

Arkadiusz Wesolowski, Jul 12 2016

Keywords

Comments

A prime 5-tuple is a constellation of five successive primes with distance 12, and is of the form (p, p+2, p+6, p+8, p+12) or (p, p+4, p+6, p+10, p+12).
Initial members p (other than 7) of prime 5-tuples of the form (p, p+4, p+6, p+10, p+12) are congruent to 97 or 187 (mod 210).
Also called prime 5-tuples of the second kind.

Crossrefs

Programs

  • MATLAB
    Primes = primes(2*10^8);
    T12 = find(Primes(5:end) - Primes(1:end-4)==12);
    T4 = find(Primes(2:end) - Primes(1:end-1)==4);
    T = intersect(T4,T12);
    Primes(reshape([T;T+1;T+2;T+3;T+4],5*numel(T),1)) % Robert Israel, Jul 14 2016
  • Magma
    lst:=[]; for p in [5..43777 by 2] do if p le 7 xor p mod 210 in {97, 187} then if IsPrime(p) then t:=[c: c in [p+4..p+12] | IsPrime(c)]; if #t eq 4 then lst:=lst cat [p] cat t; end if; end if; end if; end for; lst;
    
  • Maple
    Primes:= select(isprime, [seq(i,i=3..10^5,2)]):
    T:= select(t -> Primes[t+4]-Primes[t]=12 and Primes[t+1]-Primes[t]=4, [$1..nops(Primes)-5]):
    seq(seq(Primes[t+j],j=0..4),t=T); # Robert Israel, Jul 13 2016
  • Mathematica
    m = {0, 4, 6, 10, 12}; Union@ Flatten@ Map[# + m &, Select[Prime@ Range[10^4], Times @@ Boole@ PrimeQ[# + m] == 1 &]] (* Michael De Vlieger, Jul 13 2016 *)
    Select[Partition[Prime[Range[4600]],5,1],Differences[#]=={4,2,4,2}&]//Flatten (* Harvey P. Dale, Jun 15 2025 *)

Formula

a(5*n-4) = A022007(n).

A275515 Table read by rows: list of prime triples of the form (p, p+2, p+6).

Original entry on oeis.org

5, 7, 11, 11, 13, 17, 17, 19, 23, 41, 43, 47, 101, 103, 107, 107, 109, 113, 191, 193, 197, 227, 229, 233, 311, 313, 317, 347, 349, 353, 461, 463, 467, 641, 643, 647, 821, 823, 827, 857, 859, 863, 881, 883, 887, 1091, 1093, 1097, 1277, 1279, 1283, 1301, 1303, 1307
Offset: 1

Views

Author

Arkadiusz Wesolowski, Jul 31 2016

Keywords

Comments

A prime triple is a set of three prime numbers of the form (p, p+2, p+6) or (p, p+4, p+6).
Initial members p (other than 5) of prime triples of the form (p, p+2, p+6) are congruent to 11 or 17 (mod 30).
Also called prime triples of the first kind.

Examples

			The table starts:
5, 7, 11;
11, 13, 17;
17, 19, 23;
...
		

Crossrefs

Programs

  • Magma
    &cat[[p, p+2, p+6]: p in PrimesUpTo(1301) | (p le 5 xor p mod 30 in {11, 17}) and IsPrime(p+2) and IsPrime(p+6)];
  • Mathematica
    Prime@ Range[#, # + 2] &@ PrimePi@ Select[Prime@ Range@ 216, Times @@ Boole@ PrimeQ[# + {2, 6}] > 0 &] // Flatten (* Michael De Vlieger, Aug 02 2016 *)

Formula

a(3*n-2) = A022004(n).
Showing 1-2 of 2 results.