A251859 First appearance of prime(n) in A157480.

1, 6, 5, 10, 3, 2, 8, 7, 13, 20, 30, 28, 27, 26, 35, 58, 45, 56, 55, 21, 96, 142, 53, 93, 262, 14, 139, 12, 195, 47, 87, 57, 214, 404, 133, 255, 81, 252, 37, 36, 187, 128, 127, 479, 75, 572, 477, 313, 70, 475, 179, 68, 241, 310, 19, 98, 115, 469, 762, 114, 234, 94, 302, 231, 1238, 229, 298, 376, 50, 161

Offset

1,2

Comments

Apparently all primes eventually appear in A157480. Note that this sequence is one-to-one map while A157480 not.

Links

Table of n, a(n) for n=1..70.

Formula

A157480(a(n)) = prime(n), or prime(a(n))+prime(n) is a square.

Example

a(3)=5 because A157480(5)=prime(3)=5 and prime(3)+prime(5)=5+11=16=4^2,
a(4)=10 because A157480(10)=prime(4)=7 and prime(4)+prime(10)=7+29=36=6^2.

Crossrefs

Cf. A157480.

Sequence in context: A073230 A134881 A229983 * A100884 A309549 A187892

Adjacent sequences: A251856 A251857 A251858 * A251860 A251861 A251862

Keyword

nonn

Author

Zak Seidov, Dec 10 2014

Status

approved