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A213373
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.
7
1, 3, 4, 7, 8, 10, 14, 16, 19, 20, 25, 29, 32, 38, 40, 41, 45, 50, 57, 59, 62, 63
OFFSET
1,2
COMMENTS
First differs from A212123 at a(14). For more information see A213372.
FORMULA
a(n) = A213374(n)/2.
EXAMPLE
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;
29, 32, 38, 40, 41;
45, 50, 57, 59, 62, 63;
...
CROSSREFS
Partial sums of A213371. Other versions are A210983, A212013, A212123, A213363.
Sequence in context: A210983 A213363 A212123 * A363353 A332059 A375929
KEYWORD
nonn,tabf,hard,more
AUTHOR
Omar E. Pol, Jul 16 2012
STATUS
approved