A338819 The entries in the rows of the n X n identity matrix, multiplied by the size of the matrix (n).

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

Author

Julia Zimmerman, Nov 10 2020

Keywords

• nonn
• easy

Examples

			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.
		

Crossrefs

Cf. A191747 (with 1's), A191748 (locations of nonzero terms), A056520 (start location of each matrix).

Programs

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