OFFSET
1,2
REFERENCES
Mihaly Bencze [Beneze], Smarandache recurrence type sequences, Bulletin of pure and applied sciences, Vol. 16E, No. 2, 1997, pp. 231-236.
F. Smarandache, Properties of numbers, ASU Special Collections, 1973.
LINKS
Klaus Brockhaus, Table of n, a(n) for n = 1..4900
F. Smarandache, Sequences of Numbers Involved in Unsolved Problems.
Eric Weisstein's World of Mathematics, Smarandache Sequences
MATHEMATICA
A031980 = {1}; Do[ m = Ceiling[(n-1)^(1/3)]; s = Select[ A031980, # <= m &]; ls = Length[s]; sumOfCubes = Union[ Flatten[ Table[ s[[i]]^3 + s[[j]]^3, {i, 1, ls}, {j, i+1, ls}]]]; If[ FreeQ[ sumOfCubes, n], AppendTo[ A031980, n] ], {n, 2, 77}]; A031980 (* Jean-François Alcover, Dec 14 2011 *)
PROG
(Magma) m:=77; a:=[]; a2:={}; for n in [1..m] do p:=1; u:= a2 join { x: x in a }; while p in u do p:=p+1; end while; if p gt m then break; end if; a2:=a2 join { x^3 + p^3: x in a | x^3 + p^3 le m }; Append(~a, p); end for; print a; // Klaus Brockhaus, Jul 16 2008
CROSSREFS
KEYWORD
nonn,nice,easy
AUTHOR
J. Castillo (arp(AT)cia-g.com) [Broken email address?]
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org), Sep 26 2000
Better definition from Klaus Brockhaus, Jul 16 2008
STATUS
approved