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 A046851 Numbers n such that n^2 can be obtained from n by inserting internal (but not necessarily contiguous) digits. 8
 0, 1, 10, 11, 95, 96, 100, 101, 105, 110, 125, 950, 960, 976, 995, 996, 1000, 1001, 1005, 1006, 1010, 1011, 1021, 1025, 1026, 1036, 1046, 1050, 1100, 1101, 1105, 1201, 1205, 1250, 1276, 1305, 1316, 1376, 1405, 9500, 9505, 9511, 9525, 9600, 9605, 9625 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Contains A038444.  In particular, the sequence is infinite. - Robert Israel, Oct 20 2016 If n is any positive term, then b_n(k) := n*10^k (k >= 0) is an infinite subsequence. - Rick L. Shepherd, Nov 01 2016 From Robert Israel's comment it follows that the subsequence of terms with no trailing zeros is also infinite (contains A000533). - Rick L. Shepherd, Nov 01 2016 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE 110^2 = 12100 (insert "2" and "0" into "1_1_0"). MAPLE IsSublist:= proc(a, b)   local i, bp, j;   bp:= b;   for i from 1 to nops(a) do     j:= ListTools:-Search(a[i], bp);     if j = 0 then return false fi;     bp:= bp[j+1..-1];   od;   true end proc: filter:= proc(n) local A, B;   A:= convert(n, base, 10);   B:= convert(n^2, base, 10);   if not(A[1] = B[1] and A[-1] = B[-1]) then return false fi;   if nops(A) <= 2 then return true fi;   IsSublist(A[2..-2], B[2..-2]) end proc: select(filter, [\$0..10^4]); # Robert Israel, Oct 20 2016 MATHEMATICA id[n_]:=IntegerDigits[n]; insQ[n_]:=First[id[n]]==First[id[n^2]]&&Last[id[n]]==Last[id[n^2]]; sort[n_]:=Flatten/@Table[Position[id[n^2], id[n][[i]]], {i, 1, Length[id[n]]}]; takeQ[n_]:=Module[{lst={First[sort[n][[1]]]}},    Do[     Do[      If[Last[lst]

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Last modified October 20 10:45 EDT 2019. Contains 328257 sequences. (Running on oeis4.)