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A193097
Numbers that are the concatenation of exactly one pair of nonzero squares.
3
11, 14, 19, 41, 44, 49, 91, 94, 99, 116, 125, 136, 149, 161, 169, 181, 251, 254, 259, 361, 364, 369, 416, 425, 436, 449, 464, 481, 491, 494, 499, 641, 644, 649, 811, 814, 819, 916, 925, 936, 949, 964, 981, 1001, 1004, 1009, 1100, 1121, 1144, 1169, 1196, 1211
OFFSET
1,1
COMMENTS
Subsequence of A191933; A193095(a(n)) = 1.
LINKS
EXAMPLE
161 = concat(4^2,1^2), therefore 161 is a term;
164 = concat(1^2,8^2) = concat(4^2,2^2), therefore 164 is not a term (A191933(15)=A192993(1)=164, A193095(164)=2).
MATHEMATICA
Take[Union[FromDigits[Flatten[IntegerDigits/@((#)^2)]]&/@Tuples[Range[14], 2]], 60] (* Harvey P. Dale, Jul 27 2011 *)
PROG
(Haskell)
import Data.List (elemIndices)
a193097 n = a193097_list !! (n-1)
a193097_list = elemIndices 1 $ map a193095 [0..]
CROSSREFS
Sequence in context: A216580 A114948 A191933 * A343855 A077675 A266988
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jul 17 2011
STATUS
approved