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A192993 Numbers that are in more than one way the concatenation of the decimal representation of two nonzero squares. 5
164, 1441, 1625, 1961, 2564, 4841, 12116, 14449, 16400, 25625, 46241, 48464, 115625, 116641, 144100, 148841, 160025, 162500, 163844, 169169, 184964, 193636, 196100, 256400, 361225, 368649, 466564, 484100, 493025, 961009, 973441, 1166464 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A191933.

If k is a term, then k followed by two zeros is also a term.

None of the terms < 40000000 is in more than two ways the concatenation of the decimal representation of two nonzero squares.

A038670 is a subsequence. - Reinhard Zumkeller, Jul 15 2011

LINKS

Klaus Brockhaus, Table of n, a(n) for n = 1..100 (terms < 40000000)

EXAMPLE

2564 is the concatenation of 256 and 4 as well as of 25 and 64; 256, 4, 25, 64 are squares, so 2564 is a term.

PROG

(MAGMA) SplitToSquares:=function(n); V:=[]; 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 Append(~V, [<b, a>]); end if; end for; return V; end function; [ p: p in [1..1200000] | #P gt 1 where P is SplitToSquares(p) ]; /* to obtain the splittings replace " p: " with " <p, P>: " */

(Haskell)

import Data.List (findIndices)

a192993 n = a192993_list !! (n-1)

a192993_list = findIndices (> 1) $ map a193095 [0..]

-- Reinhard Zumkeller, Jul 17 2011

CROSSREFS

Cf. A000290, A191933.

Sequence in context: A223455 A251197 A038670 * A250935 A250928 A205314

Adjacent sequences:  A192990 A192991 A192992 * A192994 A192995 A192996

KEYWORD

nonn,base

AUTHOR

Klaus Brockhaus and Zak Seidov, Jul 14 2011

STATUS

approved

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Last modified October 26 08:00 EDT 2021. Contains 348267 sequences. (Running on oeis4.)