login
A022798
a(n) = P(n) + c(n), where P(1) = 1, P(n) = (n-1)-st prime for n >= 2, c(n) = n-th number not in sequence P.
1
5, 8, 11, 14, 17, 23, 27, 32, 35, 41, 49, 52, 59, 65, 68, 73, 80, 87, 91, 99, 104, 107, 114, 119, 127, 136, 141, 145, 151, 154, 159, 175, 180, 187, 190, 201, 205, 212, 219, 224, 231, 239, 243, 254, 257, 262, 265, 279, 292, 297, 301, 307, 314, 317
OFFSET
1,1
FORMULA
a(n) = n-th composite + n-th noncomposite = A002808(n) + A008578(n). - Jaroslav Krizek, Nov 18 2009
MATHEMATICA
With[{c=Select[Range[100], CompositeQ]}, c+Join[{1}, Prime[Range[Length[c]-1]]]] (* Paolo Xausa, Nov 03 2023 *)
CROSSREFS
Sequence in context: A180486 A314387 A314388 * A022808 A104279 A184919
KEYWORD
nonn
EXTENSIONS
Wrong formula removed by Paolo Xausa, Nov 03 2023
STATUS
approved