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A066618 Both m and its reverse are one more than a square and m does not end in 0. 2
1, 2, 5, 101, 626, 5477, 7745, 10001, 1000001, 1010026, 1040401, 2217122, 2676497, 5053505, 6200101, 7946762, 100000001, 101808101, 10000000001, 10180608202, 10182828101, 10408080401, 20280608101, 26573890226, 26995147205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..53

EXAMPLE

7745 = 88^2 + 1 and 5477 = 74^2 + 1.

MATHEMATICA

dtn[L_] := Fold[10#1+#2&, 0, L] A={}; For[i=1, i>0, i++, t=dtn[Reverse[IntegerDigits[i^2+1]]]; If[IntegerQ[(t-1)^(1/2)]&&Mod[i^2, 10]=!=9, AppendTo[A, i^2+1]; Print[A]]]

PROG

(PARI) Rev(x)= { local(d, r=0); while (x>0, d=x%10; x\=10; r=r*10 + d); return(r) } { n=0; for (m=0, 10^10, k=m^2 + 1; if (k%10 && issquare(Rev(k) - 1), write("b066618.txt", n++, " ", k); if (n==100, return)) ) } \\ Harry J. Smith, Mar 13 2010

CROSSREFS

Sequence in context: A162569 A120800 A277341 * A027720 A132482 A208209

Adjacent sequences:  A066615 A066616 A066617 * A066619 A066620 A066621

KEYWORD

nonn,base

AUTHOR

Erich Friedman, Jan 08 2002

STATUS

approved

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Last modified February 22 23:03 EST 2019. Contains 320411 sequences. (Running on oeis4.)