A380782 Class number of real quadratic field Q(sqrt(prime(n))).

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 5, 3, 1

Offset: 1

Author

Steven Lu, Feb 02 2025

Keywords

• nonn

Comments

A278837 contains all primes p where the class number of Q(sqrt(p)) is larger than 1.

Examples

			For n = 22, a(22) = 3 since the class number of Q(sqrt(79)) is 3 where 79 is the 22nd prime.
		

Crossrefs

Cf. A003172, A076498, A278837.

Programs

Mathematica

Table[NumberFieldClassNumber[Sqrt[Prime[i]]], {i, 87}]