A004247 - OEIS

A004247 as a triangular array

0

0 0

0 1 0

0 2 2 0

0 3 4 3 0

0 4 6 6 4 0

0 5 8 9 8 5 0

0 6 10 12 12 10 6 0

0 7 12 15 16 15 12 7 0

0 8 14 18 20 20 18 14 8 0

0 9 16 21 24 25 24 21 16 9 0

0 10 18 24 28 30 30 28 24 18 10 0

0 11 20 27 32 35 36 35 32 27 20 11 0

0 12 22 30 36 40 42 42 40 36 30

0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 1 2 3 4 5 6 7 8 9 10 11 12

0 2 4 6 8 10 12 14 16 18 20 22

0 3 6 9 12 15 18 21 24 27 30

0 4 8 12 16 20 24 28 32 36

0 5 10 15 20 25 30 35 40

0 6 12 18 24 30 36 42

0 7 14 21 28 35 42

0 8 16 24 32 40

0 9 18 27 36

0 10 20 30

0 11

0