A228552 Square root of the absolute value of A069191(n).

1, 1, 1, 0, 1, 1, 2, 2, 0, 0, 0, 0, 0, 0, 0, 2, 2, 3, 5, 11, 8, 24, 48, 60, 56, 16, 12, 31, 155, 217, 588, 1148, 328, 164, 176, 132, 176, 395, 277, 697, 692, 191, 915, 76, 22742, 125664, 128079, 213885, 7371, 171654, 89678, 114902, 149465, 353497, 144573, 388325, 198676, 1738118, 1311164, 222898

Offset: 1

Author

Zhi-Wei Sun, Aug 25 2013

Keywords

• nonn

Comments

According to the comments of A069191, a(n) should be always integral. Note that a(2*n) is the absolute value of A228616(n) by the comments of A228591. We conjecture that a(n) > 0 for all n > 15.

Links

• Zhi-Wei Sun, Table of n, a(n) for n = 1..400

Crossrefs

Cf. A000040, A069191, A228616, A228615, A228548, A228549.

Programs

Mathematica

a[n_]:=a[n]=Sqrt[Abs[Det[Table[If[PrimeQ[i+j]==True,1,0],{i,1,n},{j,1,n}]]]]
Table[a[n],{n,1,20}]