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A180461 a(n) is the smallest number m such that sigma(m)=26^n, or 0 if m does not exist. 6

%I #12 Mar 05 2014 15:11:40

%S 1,0,0,0,312399,8911029,187131609,5560483959,126501010209,

%T 3186244194273,85514682943809,2206011586559697,55462952723504823,

%U 1577373555132452973,37744962467192492463,974816528291192900817,25345238283868264629273,658976194648474007782617,17245346702665551116114601

%N a(n) is the smallest number m such that sigma(m)=26^n, or 0 if m does not exist.

%H Max Alekseyev, <a href="/A180461/b180461.txt">Table of n, a(n) for n = 0..100</a>

%e a(4)=312399=3^2*103*337 since sigma(3^2*103*337)=(13)*(2^3*13)*(2*13^2)=2^4*13^4 and 312399 is the smallest such number.

%Y Cf. A048251, A110077, A180265, A180460, A180462, A180463, A180464.

%K nonn

%O 0,5

%A _Walter Kehowski_, Sep 06 2010

%E Terms a(17) onward from _Max Alekseyev_, Mar 04 2014

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