A338868 Number of triples of prime quadruples < 10^n.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 9, 28, 138, 613, 2799

Offset

1,12

Comments

Number of triples of prime quadruples with at most n digits. A triple of prime quadruples consists of three prime quadruples with a (minimal) distance of 120.

Links

Table of n, a(n) for n=1..18.

J. Brüggemann, The first triples of prime quadruples. [broken link]

J. Brüggemann, Calculating prime quadruples, its twins, triples and quadruples. [broken link]

Example

For n=12 the a(12)=2 solutions are [(282005261771, 282005261773, 282005261777, 282005261779), (282005261801, 282005261803, 282005261807, 282005261809) , (282005261891, 282005261893, 282005261897, 282005261899)] and [(783976940441, 783976940443, 783976940447, 783976940449), (783976940471, 783976940473, 783976940477, 783976940479), (783976940531, 783976940533, 783976940537, 783976940539)].

Crossrefs

Cf. A050258, A338866.

Sequence in context: A144239 A320951 A139006 * A213943 A153701 A176678

Adjacent sequences: A338865 A338866 A338867 * A338869 A338870 A338871

Keyword

nonn,more

Author

Hans H. Brüggemann, Nov 13 2020

Extensions

a(18) corrected by Hans H. Brüggemann, May 16 2021

Status

approved