

A138839


Concatenation of initial and final digits of nth perfect number, divided by 2.


0



33, 14, 23, 44, 18, 43, 9, 14, 13, 8, 9, 9, 13, 9, 29, 9, 48, 18, 8, 24, 8, 28, 18, 48, 8, 43, 18, 9, 9, 8, 14, 9, 43, 44, 18, 8, 43, 48, 23
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OFFSET

1,1


COMMENTS

Also, concatenation of A135617(n) and A094540(n), divided by 2.


LINKS

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


EXAMPLE

a(5)=18 because the 5th perfect number A000396(5) is 33550336 and the concatenation of initial and final digits of 33550336 is 36 and 36/2 = 18.


CROSSREFS

Cf. A000396, A073729, A135617, A094540, A138843.
Sequence in context: A123173 A147021 A200897 * A033353 A192631 A104781
Adjacent sequences: A138836 A138837 A138838 * A138840 A138841 A138842


KEYWORD

base,easy,nonn


AUTHOR

Omar E. Pol, Apr 02 2008


STATUS

approved



