Lists of nonnegative integers with constraints.

sage.combinat.integer_lists.nn.IntegerListsNN(**kwds)[source]

Lists of nonnegative integers with constraints.

This function returns the union of IntegerListsLex(n, **kwds) where \(n\) ranges over all nonnegative integers.

EXAMPLES:

sage: from sage.combinat.integer_lists.nn import IntegerListsNN
sage: L = IntegerListsNN(max_length=3, max_slope=-1)
sage: L
Disjoint union of Lazy family (<lambda>(i))_{i in Non negative integer semiring}
sage: it = iter(L)
sage: for _ in range(20):
....:     print(next(it))
[]
[1]
[2]
[3]
[2, 1]
[4]
[3, 1]
[5]
[4, 1]
[3, 2]
[6]
[5, 1]
[4, 2]
[3, 2, 1]
[7]
[6, 1]
[5, 2]
[4, 3]
[4, 2, 1]
[8]
>>> from sage.all import *
>>> from sage.combinat.integer_lists.nn import IntegerListsNN
>>> L = IntegerListsNN(max_length=Integer(3), max_slope=-Integer(1))
>>> L
Disjoint union of Lazy family (<lambda>(i))_{i in Non negative integer semiring}
>>> it = iter(L)
>>> for _ in range(Integer(20)):
...     print(next(it))
[]
[1]
[2]
[3]
[2, 1]
[4]
[3, 1]
[5]
[4, 1]
[3, 2]
[6]
[5, 1]
[4, 2]
[3, 2, 1]
[7]
[6, 1]
[5, 2]
[4, 3]
[4, 2, 1]
[8]