A213363 Total number of pairs of states of the first n subshells of the nuclear shell model in which the subshells are ordered by energy level in increasing order.

1, 3, 4, 7, 8, 10, 14, 16, 19, 20, 25, 28, 32, 33, 35, 41, 45, 47, 54, 59, 60, 63, 68, 74, 82, 85, 86, 90, 92

Offset: 1

Author

Omar E. Pol, Jun 23 2012

Keywords

• nonn
• tabf
• hard
• more

Comments

First differs from A212123 at a(12).

Examples

			Written as an irregular triangle in which row j is related to the j-th shell of nucleus. Note that row 4 has only one term. Triangle begins:
1;
3, 4;
7, 8, 10;
14;
16, 19, 20, 25;
28, 32, 33, 35, 41;
45, 47, 54, 59, 60, 63;
68, 74, 82, 85, 86, 90, 92;
...
		

Crossrefs

Partial sums of A213361. Other versions are A210983, A212013, A213373.

Cf. A018226, A212121-A212124, A213362, A213364.

Formula

a(n) = A213364(n)/2.