A116502 Squares with structure dmdmd, where d is a single digit and m a string of digits.

69696, 56722567225, 95540955409, 1108033241108033241, 1220096161220096161, 4312080784312080784, 4432132964432132964, 4880384644880384644, 9024307889024307889, 9972299169972299169, 946308825294630882529, 11542927396115429273961, 46171709584461717095844

Offset

1,1

Links

Giovanni Resta, Table of n, a(n) for n = 1..300

Erich Friedman, Puzzles of the Week [N. J. A. Sloane, Mar 12 2011]

Example

309097^2 = a(3) = 9[5540]9[5540]9.

Mathematica

w={}; Do[s = Reduce[(1 + 10^(1+e) + 100^(1+e)) d + 10 (1+10^(1+e)) x == y^2 && 0 <= x < 10^e && y>0, {x, y}, Integers]; If[s =!= False, w = Union[w, y^2 /. List@ ToRules@ s]], {e, 12}, {d, 9}]; w (* Giovanni Resta, Aug 01 2018 *)

Crossrefs

Cf. A116500, A116501, A069919.

Sequence in context: A053075 A154818 A069919 * A190934 A043600 A043858

Adjacent sequences: A116499 A116500 A116501 * A116503 A116504 A116505

Keyword

base,nonn

Author

Giovanni Resta, Feb 18 2006

Extensions

a(11)-a(13) from Giovanni Resta, Aug 01 2018

Status

approved