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A152071 Squares which when subtracted from their reverse form nonzero squares. 1
1296, 39204, 522729, 525625, 541696, 630436, 678976, 833569, 877969, 37601424, 37920964, 46812964, 52809289, 58920976, 1079056801, 1232782321, 1805485081, 1867017681, 2346821136, 3104495524, 3742013584, 4038348304, 4450490944 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..45

EXAMPLE

a(1) = 36^2 = 1296 6921 - 1296 = 5625 = 75^2

MATHEMATICA

nzQ[n_]:=Module[{s=Sqrt[IntegerReverse[n]-n]}, s!=0&&IntegerQ[s]]; Select[ Range[70000]^2, nzQ] (* The program uses the IntegerReverse function from Mathematica version 10 *) (* Harvey P. Dale, Jan 18 2016 *)

PROG

(PARI) reverse(expr)=my(v=Vec(Str(expr)), n=length(v)); concat(vector(n, i, v[n-i+1])); lista(nn) = {for (n=1, nn, if (issquare(n), rn = eval(reverse(n)); if (n!=rn && issquare(rn-n), print1(n, ", "))); ); } \\ Michel Marcus, Jun 02 2013

CROSSREFS

Sequence in context: A223596 A265471 A017140 * A223437 A183618 A017236

Adjacent sequences:  A152068 A152069 A152070 * A152072 A152073 A152074

KEYWORD

nonn,base

AUTHOR

Gaurav Kumar, Jul 24 2009

EXTENSIONS

Definition clarified by Zak Seidov, Jul 25 2009

STATUS

approved

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Last modified May 31 20:23 EDT 2020. Contains 334748 sequences. (Running on oeis4.)