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.

A328187 Number of integer partitions of n with no pair of consecutive parts relatively prime.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 4, 1, 5, 3, 8, 1, 14, 1, 16, 9, 22, 3, 38, 4, 46, 19, 58, 9, 94, 18, 106, 41, 144, 28, 221, 37, 246, 92, 318, 87, 465, 95, 530, 198, 693, 169, 963, 220, 1108, 424, 1383, 381, 1899, 492, 2216, 815, 2732, 799, 3644, 1041, 4231, 1585, 5194, 1608
Offset: 0

Views

Author

Gus Wiseman, Oct 12 2019

Keywords

Examples

			The a(1) = 1 through a(15) = 9 partitions (A..F = 10..15):
  1  2  3  4   5  6    7  8     9    A      B  C       D  E        F
           22     33      44    63   55        66         77       96
                  42      62    333  64        84         86       A5
                  222     422        82        93         A4       C3
                          2222       442       A2         C2       555
                                     622       444        644      663
                                     4222      633        662      933
                                     22222     642        842      6333
                                               822        A22      33333
                                               3333       4442
                                               4422       6422
                                               6222       8222
                                               42222      44222
                                               222222     62222
                                                          422222
                                                          2222222
		

Crossrefs

The Heinz numbers of these partitions are given by A328336.
The case of compositions is A178470.
The strict case is A328220.
Partitions with all pairs of consecutive parts relatively prime are A328172.

Programs

  • Mathematica
    Table[Length[Select[IntegerPartitions[n],!MatchQ[#,{_,x_,y_,_}/;GCD[x,y]==1]&]],{n,0,30}]