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A134741 Permutational numbers A134640 which are squares.

%I A134741 #10 Sep 04 2020 21:23:04
%S A134741 0,1,225,2500,7225,38025,106929,314721,622521,751689,1750329,3111696,
%T A134741 6002500,7568001,8168164,8282884,10323369,11682724,12517444,23367556,
%U A134741 23483716,25623844,28536964,33292900,39513796,61058596,73513476,74545956,94517284,105144516,112572100,112656996,132756484
%N A134741 Permutational numbers A134640 which are squares.
%H A134741 Robert Israel, <a href="/A134741/b134741.txt">Table of n, a(n) for n = 1..261</a>
%F A134741 a(n) = A134742(n)^2.
%p A134741 N:= 10^10: # for terms <= N
%p A134741 extend:= proc(x, N, S, b, k)
%p A134741   local i, R;
%p A134741   R:= NULL;
%p A134741   for i in S while x + i*b^k <= N do
%p A134741     if k = 0 then
%p A134741        if issqr(x+i*b^k) then R:= R, x+i*b^k fi
%p A134741     else
%p A134741        R:= R, procname(x+i*b^k, N, subs(i=NULL, S), b, k-1)
%p A134741     fi
%p A134741   od;
%p A134741   R
%p A134741 end proc:
%p A134741 f:= (b, N) -> extend(0, N, [$0..(b-1)], b, b-1):
%p A134741 R:= 0:
%p A134741 for b from 2 while b^(b-2) < N do
%p A134741   R:= R, f(b, N);
%p A134741 od:
%p A134741 sort([R]); # Robert Israel, Sep 04 2020
%t A134741 a = {}; b = {}; Do[AppendTo[b, n]; w = Permutations[b]; Do[j = FromDigits[w[[m]], n + 1]; If[IntegerQ[j^(1/2)], AppendTo[a, j]], {m, 1, Length[w]}], {n, 0, 7}]; a
%Y A134741 Cf. A134640, A134641, A134642, A134643, A134644, A023811, A134742.
%K A134741 nonn
%O A134741 1,3
%A A134741 _Artur Jasinski_, Nov 07 2007
%E A134741 Corrected and more terms from _Robert Israel_, Sep 04 2020