A375924 Number A(n,k) of partitions of [n] such that the element sum of each block is one more than a multiple of k; square array A(n,k), n>=0, k>=0, read by antidiagonals.
1, 1, 1, 1, 1, 0, 1, 1, 2, 0, 1, 1, 1, 5, 0, 1, 1, 0, 2, 15, 0, 1, 1, 0, 0, 4, 52, 0, 1, 1, 0, 1, 1, 10, 203, 0, 1, 1, 0, 1, 2, 3, 28, 877, 0, 1, 1, 0, 0, 0, 3, 9, 96, 4140, 0, 1, 1, 0, 0, 0, 0, 1, 17, 320, 21147, 0, 1, 1, 0, 0, 0, 1, 1, 8, 108, 1436, 115975, 0
Offset: 0
Examples
A(5,2) = 10: 12345, 124|3|5, 12|34|5, 12|3|45, 14|23|5, 1|234|5, 1|23|45, 14|25|3, 1|245|3, 1|25|34. A(6,3) = 9: 136|25|4, 13|256|4, 13|25|46, 16|235|4, 1|2356|4, 1|235|46, 16|25|34, 1|256|34, 1|25|346. A(7,4) = 8: 14|23|5|67, 1|234|5|67, 1|23|45|67, 1|23|467|5, 14|27|36|5, 1|247|36|5, 1|27|346|5, 1|27|36|45. A(8,5) = 1: 12345678. A(8,8) = 4: 18|27|36|45, 1|278|36|45, 1|27|368|45, 1|27|36|458. A(9,6) = 87: 123469|58|7, 12349|568|7, 12349|58|67, 123568|49|7, ..., 1|25|346789, 16|289|3457, 1|2689|3457, 1|289|34567. A(9,8) = 5: 18|27|36|45|9, 1|278|36|45|9, 1|27|368|45|9, 1|27|36|458|9, 1|27|36|45|89. A(9,10) = 1: 1|29|38|47|56. Square array A(n,k) begins: 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ... 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ... 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, ... 0, 5, 2, 0, 1, 1, 0, 0, 0, 0, 0, ... 0, 15, 4, 1, 2, 0, 0, 0, 1, 1, 0, ... 0, 52, 10, 3, 3, 0, 1, 1, 0, 0, 0, ... 0, 203, 28, 9, 1, 1, 3, 0, 0, 1, 1, ... 0, 877, 96, 17, 8, 15, 4, 0, 1, 1, 0, ... 0, 4140, 320, 108, 32, 1, 0, 1, 4, 0, 0, ... 0, 21147, 1436, 324, 51, 10, 87, 72, 5, 0, 1, ... 0, 115975, 5556, 1409, 621, 50, 1, 0, 0, 1, 5, ...
Links
- Alois P. Heinz, Antidiagonals n = 0..40, flattened
- Wikipedia, Partition of a set
Comments