Alternating sum of 12-gonal (or dodecagonal) numbers.

Terms

a(0) =0a(1) =-1a(2) =11a(3) =-22a(4) =42a(5) =-63a(6) =93a(7) =-124a(8) =164a(9) =-205a(10) =255a(11) =-306a(12) =366a(13) =-427a(14) =497a(15) =-568a(16) =648a(17) =-729a(18) =819a(19) =-910a(20) =1010a(21) =-1111a(22) =1221a(23) =-1332a(24) =1452a(25) =-1573a(26) =1703a(27) =-1834a(28) =1974a(29) =-2115