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%I #21 Jan 19 2021 21:38:04
%S 1,1729,2989441,5168743489,8936757492481,15451653704499649,
%T 26715909255079893121,46191807102033135206209,
%U 79865634479415290771535361,138087682014909037743984639169,238753602203777726259349441123201,412804978210331688702415183702014529
%N Powers of 1729, the Hardy-Ramanujan number.
%C About 1729: "No," said Ramanujan, "It is a very interesting number..."
%D David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1997, 153.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/1729_(number)">1729 (number)</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1729).
%F a(n) = 1729^n.
%F From _Chai Wah Wu_, Jan 19 2021: (Start)
%F a(n) = 1729*a(n-1) for n > 0.
%F G.f.: 1/(1 - 1729*x). (End)
%t 1729^Range[0, 9] (* _Alonso del Arte_, Oct 18 2014 *)
%o (PARI) a(n)=1729^n \\ _Charles R Greathouse IV_, Jan 20 2014
%Y Cf. A001235, A011541, A133019, A133029, A138129.
%K nonn,easy
%O 0,2
%A _Omar E. Pol_, Mar 09 2008