1,4

a(n) = n - A247892(n).

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

a(n) = A000720(A069213(n)) - A001221(n).

(Haskell)

a247815 = sum . map a010051' . a077581_row

Cf. A000720, A001221, A010051, A069213, A077581, A247892.

Sequence in context: A155981 A057958 A225411 * A057953 A129231 A166477

Adjacent sequences: A247812 A247813 A247814 * A247816 A247817 A247818

nonn

Reinhard Zumkeller, Sep 26 2014

approved