A138843 Concatenation of initial and final digits of n-th perfect number.

66, 28, 46, 88, 36, 86, 18, 28, 26, 16, 18, 18, 26, 18, 58, 18, 96, 36, 16, 48, 16, 56, 36, 96, 16, 86, 36, 18, 18, 16, 28, 18, 86, 88, 36, 16, 86, 96, 46

Offset

1,1

Comments

Also, concatenation of A135617(n) and A094540(n).

Links

Table of n, a(n) for n=1..39.

Example

a(5)=36 because the 5th perfect number A000396(5) is 33550336 and the concatenation of initial and final digits of 33550336 is 36.

Crossrefs

Cf. A000396, A073729, A135617, A094540, A138840, A138841, A138842, A138844.

Sequence in context: A157631 A085503 A271711 * A033386 A008896 A071712

Adjacent sequences: A138840 A138841 A138842 * A138844 A138845 A138846

Keyword

base,nonn,less

Author

Omar E. Pol, Apr 02 2008

Status

approved