Totient numbers (A002202) of the form 1 + k + k^2 + k^3 +...+ k^i (i > 1, k > 1).

Terms

a(0) =40a(1) =156a(2) =400a(3) =820a(4) =1464a(5) =2380a(6) =3280a(7) =3616a(8) =3906a(9) =5220a(10) =7240a(11) =9724a(12) =12720a(13) =19608a(14) =20440a(15) =25260a(16) =30784a(17) =37060a(18) =60880a(19) =66430a(20) =70644a(21) =81400a(22) =93196a(23) =97656a(24) =106080a(25) =120100a(26) =135304a(27) =151740a(28) =169456a(29) =177156