1,2

a(A005117(n)) = A090705(n) and a(A013929(n)) = A013929(n);

A102511(n) = Sum(A008683(a(k)): k<=n) <= 1;

permutation of the natural numbers with inverse A102513;

A102512 = a(a(n)).

Table of n, a(n) for n=1..72.

Index entries for sequences that are permutations of the natural numbers

Cf. A005117, A008966.

Sequence in context: A068457 A299402 A286451 * A206225 A208507 A216153

Adjacent sequences: A102507 A102508 A102509 * A102511 A102512 A102513

nonn

Reinhard Zumkeller, Jan 13 2005

approved