Least semiprime m such that the previous semiprime is m - A215231(n).

Terms

a(0) =6a(1) =9a(2) =14a(3) =21a(4) =33a(5) =106a(6) =611a(7) =1437a(8) =2701a(9) =6583a(10) =16078a(11) =17993a(12) =32807a(13) =35135a(14) =36019a(15) =340941a(16) =1069595a(17) =1589717a(18) =3586913a(19) =5835265a(20) =139139963a(21) =251306399a(22) =285074774a(23) =327023293a(24) =751412039a(25) =981270997a(26) =2655397729a(27) =5238281053a(28) =6498130471a(29) =8512915685