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A066742 Square numbers not divisible by 10 whose reverse is pentagonal. 0
0, 1, 529, 1089, 2116, 6241, 103041, 26222944225, 2648772525025, 6262611355441, 62443279235236, 1520130841269290490409 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
EXAMPLE
925 is pentagonal and 529 is square
MATHEMATICA
dtn[L_] := Fold[10#1+#2&, 0, L] A={0}; For[i=1, i>0, i++, t=i(3i-1)/2; r=dtn[Reverse[IntegerDigits[t]]]; If[IntegerQ[Sqrt[r]]&&Mod[t, 10]>0, AppendTo[A, r]; Print[A]]]
CROSSREFS
Sequence in context: A020289 A274932 A082409 * A067475 A052074 A112079
KEYWORD
base,more,nonn
AUTHOR
Erich Friedman, Jan 16 2002
EXTENSIONS
Description clarified, offset corrected, and a(12) added by Lars Blomberg, May 29 2011
STATUS
approved

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Last modified July 15 02:08 EDT 2024. Contains 374323 sequences. (Running on oeis4.)