A022953 a(n) = a(n-1) + c(n+1) for n >= 3, a( ) increasing, given a(1)=1, a(2)=7; where c( ) is complement of a( ).

1, 7, 12, 18, 26, 35, 45, 56, 69, 83, 98, 114, 131, 150, 170, 191, 213, 236, 260, 285, 312, 340, 369, 399, 430, 462, 495, 529, 565, 602, 640, 679, 719, 760, 802, 845, 889, 935, 982, 1030, 1079, 1129, 1180, 1232, 1285, 1339, 1394, 1451, 1509, 1568

Offset

1,2

Comments

Here "complement" refers to the numbers not in the sequence.

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Mathematica

Fold[Append[#1, #1[[-1]] + Complement[Range[Max@#1 + 3], #1][[#2 + 1]]] &, {1, 7}, Range[3, 50]] (* Ivan Neretin, Apr 05 2016 *)

Crossrefs

Essentially same as A005228.

Sequence in context: A142337 A131912 A247159 * A030714 A190036 A061141

Adjacent sequences: A022950 A022951 A022952 * A022954 A022955 A022956

Keyword

nonn

Author

Clark Kimberling

Status

approved