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A338819
The entries in the rows of the n X n identity matrix, multiplied by the size of the matrix (n).
0
1, 2, 0, 0, 2, 3, 0, 0, 0, 3, 0, 0, 0, 3, 4, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4, 0, 0, 0, 0, 4, 5, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 5, 6, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 6, 7, 0
OFFSET
1,2
EXAMPLE
For every identity matrix of size n starting with n=1, append n*(each entry of each row of the matrix), e.g., n=1 -> 1, n=2 -> 2,0,0,2, so the first 5 terms of the sequence are 1,2,0,0,2.
PROG
(Python)
import numpy as np
def n_id_sequence(iterations):
sequence = []
for i in range(1, iterations+1):
matrix = i*(np.identity(i))
for row in matrix:
for entry in row:
sequence.append(int(entry))
return sequence
CROSSREFS
Cf. A191747 (with 1's), A191748 (locations of nonzero terms), A056520 (start location of each matrix).
Sequence in context: A033747 A087611 A282133 * A153869 A128541 A122908
KEYWORD
nonn,easy
AUTHOR
Julia Zimmerman, Nov 10 2020
STATUS
approved