A180233 The sequence gives prime numbers formed from the sum of the squares of composite numbers and the corresponding prime numbers.

157, 353, 431, 619, 967, 1871, 2243, 4567, 5417, 7001, 11633, 18503, 24359, 24989, 26927, 29633, 34667, 35419, 39293, 40883, 47653, 52127, 73121, 74201, 83219, 89087, 98911, 110569, 114617, 118717, 124301, 144883, 155747, 158927, 163741

Offset

1,1

Links

Table of n, a(n) for n=1..35.

Example

Add the square of first composite (4*4) and first prime (2) = 18; add the square of the second composite (6*6) and second prime (3) = 39 - and so forth. First prime found is 157 = A002808(6)^2 + A000040(6) = 12^2 + 13. - Leonard Galitz, Jun 15 2013

Prog

(REX) keep(add(square(composite(1, 100)), prime(1, 100)), isprime) - Leonard Galitz
(PARI) lista(nn) = {for (n = 1, nn, if (isprime(p = A002808(n)^2 + prime(n)), print1(p, ", ")); ); } \\ Michel Marcus, Jun 15 2013

Crossrefs

Sequence in context: A234364 A060974 A073277 * A096708 A142833 A142478

Adjacent sequences: A180230 A180231 A180232 * A180234 A180235 A180236

Keyword

nonn

Author

Leonard Galitz (grovehall1938(AT)comcast.net), Aug 18 2010

Extensions

More terms from Michel Marcus, Jun 15 2013

Status

approved