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The sequence gives prime numbers formed from the sum of the squares of composite numbers and the corresponding prime numbers.
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%I #15 Nov 04 2024 18:35:35

%S 157,353,431,619,967,1871,2243,4567,5417,7001,11633,18503,24359,24989,

%T 26927,29633,34667,35419,39293,40883,47653,52127,73121,74201,83219,

%U 89087,98911,110569,114617,118717,124301,144883,155747,158927,163741

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

%e 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

%o (Rexx) keep(add(square(composite(1,100)),prime(1,100)),isprime) - Leonard Galitz

%o (PARI) lista(nn) = {for (n = 1, nn, if (isprime(p = A002808(n)^2 + prime(n)), print1(p, ", ")););} \\ _Michel Marcus_, Jun 15 2013

%K nonn

%O 1,1

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

%E More terms from _Michel Marcus_, Jun 15 2013