A213373 - OEIS

%I #13 Sep 03 2012 07:13:16

%S 1,3,4,7,8,10,14,16,19,20,25,29,32,38,40,41,45,50,57,59,62,63

%N 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.

%C First differs from A212123 at a(14). For more information see A213372.

%H MIT OpenCourseWare, <a href="http://www.flickr.com/photos/mitopencourseware/3772864128/in/set-72157621892931990">Energy Levels of Nucleons in a Smoothly-Varying Potential Well</a>

%F a(n) = A213374(n)/2.

%e 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:

%e 1;

%e 3, 4;

%e 7, 8, 10;

%e 14;

%e 16, 19, 20, 25;

%e 29, 32, 38, 40, 41;

%e 45, 50, 57, 59, 62, 63;

%e ...

%Y Partial sums of A213371. Other versions are A210983, A212013, A212123, A213363.

%Y Cf. A018226, A213372, A213374.

%K nonn,tabf,hard,more

%O 1,2

%A _Omar E. Pol_, Jul 16 2012