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A191933 Numbers that are the concatenation of the decimal representation of two nonzero squares. 8
11, 14, 19, 41, 44, 49, 91, 94, 99, 116, 125, 136, 149, 161, 164, 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A193096; A193095(a(n)) > 0; A038670, A039686, A167535, A192993, A193097 and A193144 are subsequences. [Reinhard Zumkeller, Jul 17 2011]

LINKS

Klaus Brockhaus, Table of n, a(n) for n = 1..1000

MATHEMATICA

Take[Union[Flatten[Table[FromDigits[Flatten[{IntegerDigits[m^2], IntegerDigits[n^2]}]], {m, 20}, {n, 20}]]], 50] (* Alonso del Arte, Aug 11 2011 *)

squareQ[n_] := IntegerQ[Sqrt[n]]; okQ[n_] := MatchQ[IntegerDigits[n], {a__ /; squareQ[FromDigits[{a}]], b__ /; First[{b}] > 0 && squareQ[FromDigits[ {b}]]}]; Select[Range[2000], okQ] (* Jean-Fran├žois Alcover, Dec 13 2016 *)

PROG

(MAGMA) CheckSplits:=function(n); v:=false; S:=Intseq(n); for j in [1..#S-1] do A:=[ S[k]: k in [1..j] ]; a:=Seqint(A); B:=[ S[k]: k in [j+1..#S] ]; b:=Seqint(B); if a gt 0 and A[#A] gt 0 and IsSquare(a) and IsSquare(b) then v:=true; end if; end for; return v; end function; [ p: p in [1..1200] | CheckSplits(p) ];

(Haskell)

import Data.List (findIndices)

a191933 n = a191933_list !! (n-1)

a191933_list = findIndices (> 0) $ map a193095 [0..]

-- Reinhard Zumkeller, Jul 17 2011

CROSSREFS

Cf. A000290, A192993.

Sequence in context: A163672 A216580 A114948 * A193097 A343855 A077675

Adjacent sequences:  A191930 A191931 A191932 * A191934 A191935 A191936

KEYWORD

nonn,base,easy

AUTHOR

Klaus Brockhaus, Jun 19 2011

STATUS

approved

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Last modified October 23 04:06 EDT 2021. Contains 348211 sequences. (Running on oeis4.)