Composite numbers k such that the sum of all composites <= k is composite.

Terms

a(0) =4a(1) =6a(2) =8a(3) =9a(4) =12a(5) =14a(6) =15a(7) =16a(8) =18a(9) =20a(10) =21a(11) =22a(12) =25a(13) =26a(14) =28a(15) =30a(16) =33a(17) =34a(18) =35a(19) =36a(20) =38a(21) =39a(22) =40a(23) =42a(24) =44a(25) =45a(26) =46a(27) =48a(28) =49a(29) =50