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A162945
Numbers k with squares that are concatenations k^2 = x//y such that x is an anagram of y.
1
836, 3911, 6926, 6941, 9701, 9786, 32119, 35268, 39011, 40104, 40645, 40991, 41489, 42849, 43204, 45743, 49498, 50405, 50705, 54335, 55493, 57089, 57111, 59872, 60406, 62043, 64396, 64671, 66979, 68595, 69028, 69907, 70107, 72475, 73625, 75926, 76279
OFFSET
1,1
COMMENTS
Cases with leading zeros in y, for example 51674^2 = 2670202276, are not admitted.
Contains 4*10^(2*k)+10^k+4, 5*10^(2*k)+4*10^k+5, 5*10^(2*k)+7*10^k+5,
6*10^(2*k)+4*10^k+6, 7*10^(2*k)+10^k+7 for k >= 2. In particular, the sequence is infinite. - Robert Israel, Apr 16 2019
LINKS
EXAMPLE
836^2 = 698896 = 698//896 and 698 is an anagram of 896.
MAPLE
isA162945 := proc(n) local n2, x, y ; n2 := convert(n^2, base, 10) ; if nops(n2) mod 2 = 0 then if op(nops(n2)/2, n2) <> 0 then y := sort( [op(1..nops(n2)/2, n2)] ); x := sort( [op(nops(n2)/2+1..nops(n2), n2)] ); RETURN( x = y) ; else false; fi; else false; fi; end:
for n from 1 to 90000 do if isA162945(n) then printf("%d, \n", n) ; fi; od: # R. J. Mathar, Jul 21 2009
MATHEMATICA
Cases[If[OddQ@(l = IntegerLength@(p = #^2)),
Nothing, {#, Partition[IntegerDigits@p, l/2]}] & /@
Range@500000, {a_, _?(Sort@#[[1]] == Sort@#[[2]] && #[[2]][[1]] != 0 &)} :> a] (* Hans Rudolf Widmer, Jul 19 2024 *)
CROSSREFS
Sequence in context: A113856 A245947 A235288 * A138850 A357326 A322524
KEYWORD
nonn,base
AUTHOR
Claudio Meller, Jul 18 2009
EXTENSIONS
Keyword:base added by R. J. Mathar Jul 21 2009
STATUS
approved