

A138841


Concatenation of initial and final digit of nth Mersenne prime A000668(n).


8



33, 77, 31, 17, 81, 11, 57, 27, 21, 61, 17, 17, 61, 57, 17, 17, 41, 21, 11, 27, 41, 31, 21, 41, 41, 41, 81, 57, 57, 51, 77, 17, 11, 47, 81, 61, 11, 41, 91, 17, 27, 17, 31, 11, 27, 11, 31
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..47.


FORMULA

a(n) = A073729(A000668(n)).  Michel Marcus, Apr 17 2018


EXAMPLE

a(5)=81 because the 5th Mersenne prime is 8191, A000668(5)=8191.


CROSSREFS

Cf. A000668, A073729, A080172, A135613, A138840, A138842, A138843.
Sequence in context: A049012 A137187 A134037 * A248979 A246409 A211837
Adjacent sequences: A138838 A138839 A138840 * A138842 A138843 A138844


KEYWORD

base,nonn,more,less


AUTHOR

Omar E. Pol, Apr 01 2008


EXTENSIONS

a(40)a(47) from Ivan Panchenko, Apr 17 2018


STATUS

approved



