A pattern number (3_{k})2(6_{2k+2})(3_{2k+1})2(6_{k})7
with k=6305 whose square yields a concatenation of two
consecutives in reverse order of the form (T+1)_(T).
E.g.: 326666333267^2 = 106710893290_106710893289.
Source see file em152.htm at www.worldofnumbers.com.
PRP to base 3, 5 and 7 using PFGW Version 20031222.

To be completed...