A106563 Numbers n such that n^2 is not the sum of two primes.

1, 11, 17, 23, 25, 31, 39, 41, 45, 51, 53, 57, 59, 65, 67, 73, 79, 81, 83, 85, 87, 91, 95, 97, 99, 101, 105, 109, 111, 113, 115, 123, 125, 129, 133, 137, 141, 143, 147, 149, 151, 153, 157, 159, 163, 165, 167, 171, 175, 179, 181, 185, 187, 189, 193, 195, 197, 199, 201

Offset

1,2

Links

Table of n, a(n) for n=1..59.

Formula

a(n) = SQRT(A106562(n)).

Example

a(3)=17 because the third square which is not the sum of two primes (289=17^2) is the 17th one in the succession of the perfect squares (thus: index 17).

Crossrefs

Cf. A106544-A106548, A106562-A106564, A106571, A106573-A106575, A106577.

Sequence in context: A184551 A190039 A066074 * A106574 A171125 A156781

Adjacent sequences: A106560 A106561 A106562 * A106564 A106565 A106566

Keyword

nonn

Author

Alexandre Wajnberg, May 09 2005

Extensions

Extended by Ray Chandler, May 12 2005

Status

approved