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.

A078870 Decimal concatenations of the 38 quintuples (d1,d2,d3,d4,d5) with elements in {2,4,6} for which there exists a prime p >= 7 such that the differences between the 6 consecutive primes starting with p are (d1,d2,d3,d4,d5).

Original entry on oeis.org

24246, 24626, 24662, 26424, 26426, 26462, 26466, 26642, 26646, 26664, 42424, 42462, 42466, 42646, 46246, 46264, 46266, 46626, 46662, 62462, 62642, 62646, 62664, 62666, 64242, 64246, 64264, 64624, 64626, 64662, 64666, 66264, 66266, 66424, 66462, 66466, 66626, 66646
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Examples

			66646 is in the sequence because 3301, 3307, 3313, 3319, 3323 and 3329 are consecutive primes with differences (6,6,6,4,6).
		

Crossrefs

Programs

  • Mathematica
    With[{k = 5}, FromDigits /@ Select[Tuples[Range[2, 6, 2], k], Function[m, Count[Range[k - 1, 10^4], n_ /; Times @@ Boole@ Map[PrimeQ, Prime@ n + Accumulate@ m] == 1] > 0]]] (* Michael De Vlieger, Mar 25 2017 *) (* or *)
    FromDigits /@ Union@ Select[ Partition[ Differences@ Prime[Range[4, 9000]], 5, 1], Max@ # <= 6 &] (* Giovanni Resta, Mar 25 2017 *)

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078871 Decimal concatenations of the 6-tuples (d1,d2,d3,d4,d5,d6) with elements in {2,4,6} for which there exists a prime p >= 7 such that the differences between the 7 consecutive primes starting with p are (d1,d2,d3,d4,d5,d6).

Original entry on oeis.org

242462, 246264, 246266, 246626, 264242, 264246, 264264, 264626, 264666, 266424, 266466, 266646, 424626, 424662, 462462, 462642, 462646, 462664, 462666, 466264, 466266, 466626, 624626, 626424, 626426, 626462, 626466, 626642, 626646, 626664, 642462, 642466, 642646, 646246, 646264, 646266, 646626, 646662, 662642, 662646, 662664, 662666, 664246, 664626, 664662, 666264, 666266, 666462
Offset: 1

Views

Author

Labos Elemer, Dec 20 2002

Keywords

Examples

			For 424662, the first 2 primes with the given differences are 37 and 25767877. For 646626, the least start prime is 6268957.
		

Crossrefs

The least primes corresponding to the 6-tuples are in A078874. The same primes, in increasing order, are in A078875. The similarly defined quadruples and quintuples are in A078868 and A078870. Cf. A001223, A078869.

Extensions

Edited by Dean Hickerson, Dec 21 2002
Showing 1-2 of 2 results.