0,25

a(n) = #{k: A008963(k) = 4 and 0<=k<=n};

a(A105504(n)) = a(A105504(n) - 1) + 1;

n = A105511(n) + A105512(n) + A105513(n) + a(n) + A105515(n) + A105516(n) + A105517(n) + A105518(n) + A105519(n).

Table of n, a(n) for n=0..104.

Cf. A000030, A000045.

Sequence in context: A105518 A111896 A105515 * A214081 A194338 A176170

Adjacent sequences: A105511 A105512 A105513 * A105515 A105516 A105517

nonn,base

Reinhard Zumkeller, Apr 11 2005

approved