Sum of absolute values of coefficients of expansion of (1-x)(1-x^2)(1-x^3)...(1-x^n).

Terms

a(0) =1a(1) =2a(2) =4a(3) =6a(4) =8a(5) =12a(6) =16a(7) =20a(8) =28a(9) =36a(10) =44a(11) =54a(12) =72a(13) =92a(14) =104a(15) =138a(16) =176a(17) =212a(18) =268a(19) =332a(20) =416a(21) =508a(22) =628a(23) =776a(24) =968a(25) =1192a(26) =1480a(27) =1836a(28) =2288a(29) =2812