The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A249633 Numbers whose squares remain squares when prepended with 1 and appended with 25 in base 10. 4
 285290, 37501930, 5986235584, 6402200716, 7097946940, 2189113296470, 533822715205534, 120542200191255266, 175167560462651234, 1035777761966641262300, 55811056504696202088334, 87383897508158263975600, 342433449090893699643070, 356558269841736892522930 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Square roots of A249621. a(34) >= 10^50. - Hiroaki Yamanouchi, Nov 22 2014 a(34) = 3894512793630238968387948459831502376753914222969510. - Giovanni Resta, Mar 08 2017 LINKS Chai Wah Wu and Hiroaki Yamanouchi, Table of n, a(n) for n = 1..33 (terms a(1)-a(27) from Chai Wah Wu) EXAMPLE 81390384100 = 285290^2 and 18139038410025 = 4258995^2. MATHEMATICA a249633Q[n_Integer] :=   Module[{m, t}, m := ToString[n^2];    IntegerQ[Sqrt[ToExpression["1" <> m <> "25"]]]]; Select[Range[300000], a249633Q[#] &] (* Michael De Vlieger, Nov 06 2014 *) CROSSREFS Cf. A249621. Sequence in context: A214357 A096519 A334311 * A157112 A272444 A250824 Adjacent sequences:  A249630 A249631 A249632 * A249634 A249635 A249636 KEYWORD nonn,base AUTHOR Chai Wah Wu, Nov 02 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 7 14:09 EDT 2021. Contains 343650 sequences. (Running on oeis4.)