90 is carréphylic - approach of √90=3√10 ~ 9.4868329805

Subsequent approximations of √90 - the position of a fraction indicates whether it is over or under the root-value.
10123456789191801992182372562752943133323517216840...
0111111111121921232527293133353776721...

Diophantine equation:s2-90p2 = 1
d = distance to nearest square N2:+9
Smallest non-trivial s:(2*81+9)/9rational: 19actual: 19⇒ F=38
Smallest non-trivial p:2*9/9rational: 2actual: 2⇒ primus foldage=2
v-value qt-blocks:92-90*12:-9
Number of series:11

Cross multiplying the red-green pairs renders subsequent solutions of the diophantine equation.
s119721...
p0276...

In the numerator:U(1,19)38=1/2*U(2,38)38-half the secundus of 38.
In the denominator:U(0,2)38=2*U(0,1)38-the 2-fold primus of 38.
as well as ...
In the numerator:U(0,180)38=180*U(0,1)38-the 90*2-fold primus of 38.
In the denominator:U(1,19)38=1/2*U(2,38)38-half the secundus of 38.
and ...
In the numerator:U(-9,9)38=9*U(-1,1)38-the 9-fold quartus of 38.
In the denominator:U(1,1)38=-the tertius of 38.


23567810111213141517181920212223242627282930
31323334353738394041424344454647485051525354555657
58596061626365666768697071727374757677787980828384
858687888990919293949596979899101102103104105106107108109110