Search: id:A004068 Results 1-1 of 1 results found. %I A004068 %S A004068 0,1,7,23,54,105,181,287,428,609,835,1111,1442,1833,2289,2815,3416, %T A004068 4097,4863,5719,6670,7721,8877,10143,11524,13025,14651,16407,18298, %U A004068 20329,22505,24831,27312,29953,32759,35735,38886,42217,45733,49439 %N A004068 Number of atoms in dodecahedron with n shells. %C A004068 Also as a(n)=(1/6)*(5*n^3+n), n>0: structured pentagonal diamond numbers (vertex structure 6) (Cf. A081436 = alternate vertex; A000447 = structured diamonds; A100145 for more on structured numbers). - James A. Record (james.record(AT)gmail.com), Nov. 7, 2004. %D A004068 T. P. Martin, Shells of atoms, Phys. Reports, 273 (1996), 199-241, eq. (3). %F A004068 5*C(n + 1, 3) + C(n, 1). Or, with different offset, 5*n^3/6+n/6. %F A004068 a(n) = sum(1 + sum(5*n)) = sum (A005891) - Xavier Acloque Oct 08 2003 %Y A004068 1/12*t*(n^3-n)+n for t = 2, 4, 6, ... gives A004006, A006527, A006003, A005900, A004068, A000578, A004126, A000447, A004188, A004466, A004467, A007588, A062025, A063521, A063522, A063523. %Y A004068 Cf. A005891, A006322. %Y A004068 Sequence in context: A147121 A098334 A038796 this_sequence A022815 A027116 A151718 %Y A004068 Adjacent sequences: A004065 A004066 A004067 this_sequence A004069 A004070 A004071 %K A004068 nonn %O A004068 0,3 %A A004068 Albert D. Rich (Albert_Rich(AT)msn.com). Search completed in 0.002 seconds