Group the composite numbers so that the sum of the n-th group is a multiple of the n-th prime: (4), (6), (8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22), (24, 25), (26, 27, 28, 30, 32), (33, 34, ...), ... Sequence gives sum of n-th group.
A074124
Group the composite numbers so that the sum of the n-th group is a multiple of the n-th prime: (4), (6), (8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22), (24, 25), (26, 27, 28, 30, 32), (33, 34, ...), ... Sequence gives sum of n-th group.
Terms
- a(0) =4a(1) =6a(2) =165a(3) =49a(4) =143a(5) =962a(6) =884a(7) =1577a(8) =6992a(9) =3161a(10) =3565a(11) =1924a(12) =8159a(13) =18834a(14) =41877a(15) =2332a(16) =2360a(17) =2867a(18) =34304a(19) =184245a(20) =70883a(21) =15405a(22) =8798a(23) =107512a(24) =216213a(25) =136855a(26) =49131a(27) =31030a(28) =105621a(29) =783994
External references
- oeis: A074124