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A008318
Smallest number strictly greater than previous one which is the sum of squares of two previous distinct terms (a(1)=1, a(2)=2).
5
1, 2, 5, 26, 29, 677, 680, 701, 842, 845, 866, 1517, 458330, 458333, 458354, 459005, 459170, 462401, 462404, 462425, 463076, 463241, 491402, 491405, 491426, 492077, 492242, 708965, 708968, 708989, 709640, 709805, 714026, 714029, 714050, 714701
OFFSET
1,2
COMMENTS
A003095 is a subsequence apart from the initial term. - Reinhard Zumkeller, Jan 17 2008
The subsequence of primes begins: 2, 5, 29, 677, 701, 458333, 462401, 492077, 708989, 714029, ... - Jonathan Vos Post, Nov 21 2012
REFERENCES
F. Smarandache, Definitions solved and unsolved problems, conjectures and theorems in number theory and geometry, edited by M. Perez, Xiquan Publishing House 2000
F. Smarandache, Sequences of Numbers Involved in Unsolved Problems, Hexis, Phoenix, 2006.
LINKS
Mihaly Bencze [Beneze], Smarandache Recurrence Type Sequences, in Bull. Pure Appl. Sciences, Vol. 16E, No. 2, 231-236, 1997.
Eric Weisstein's World of Mathematics, Smarandache Sequences.
MATHEMATICA
a[1]=1; a[2]=2; a[n_] := a[n] = First[ Select[ Sort[ Flatten[ Table[a[j]^2 + a[k]^2, {j, 1, n-1}, {k, j+1, n-1}]]], # > a[n-1] & , 1]]; Table[a[n], {n, 1, 36}](* Jean-François Alcover, Nov 10 2011 *)
PROG
(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a008318 n = a008318_list !! (n-1)
a008318_list = f [1] (singleton 1) where
f xs s =
m : f (m:xs) (foldl (flip insert) s' (map (+ m^2) (map (^ 2) xs)))
where (m, s') = deleteFindMin s
-- Reinhard Zumkeller, Aug 15 2011
CROSSREFS
Cf. A192476.
Sequence in context: A370555 A120767 A051771 * A365324 A204275 A160048
KEYWORD
nonn,easy,nice
AUTHOR
R. Muller
EXTENSIONS
More terms from David W. Wilson
STATUS
approved