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 A066702 Square numbers whose reverse is triangular with the same number of digits. 3
 0, 1, 1306449, 1044000721, 12957041241, 1019072079081, 1174279984164, 6454272356676, 65036563475625, 67624587155889, 123826990849454025, 170448128872993657764, 19198191503444720114404 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS The sequence of corresponding triangular numbers is A066703. - Robert G. Wilson v, Jan 31 2011 LINKS EXAMPLE 9446031 is triangular and 1306449 is a square. MATHEMATICA lst = {0}; For[i = 1, i > 0, i++, s = i^2; t = FromDigits@ Reverse@ IntegerDigits@ s; If[ IntegerQ@ Sqrt[8 t + 1] && Mod[s, 10] > 0, AppendTo[lst, s]; Print@ lst]] CROSSREFS Cf. A066703, A181412. - Harvey P. Dale, Jan 30 2011 Sequence in context: A254187 A253799 A186138 * A261731 A141592 A234710 Adjacent sequences:  A066699 A066700 A066701 * A066703 A066704 A066705 KEYWORD base,more,nonn AUTHOR Erich Friedman, Jan 14 2002 EXTENSIONS a(12)-a(13) from and offset corrected by Giovanni Resta, Jun 20 2015 STATUS approved

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Last modified December 8 08:49 EST 2019. Contains 329862 sequences. (Running on oeis4.)