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A045637 Primes of the form p^2+4, where p is prime. +0
11
13, 29, 53, 173, 293, 1373, 2213, 4493, 5333, 9413, 10613, 18773, 26573, 27893, 37253, 54293, 76733, 85853, 94253, 97973, 100493, 120413, 139133, 214373, 237173, 253013, 299213, 332933, 351653, 368453, 375773, 458333, 552053, 619373 (list; graph; listen)
OFFSET

1,1

COMMENT

The only prime of the form p^2+2 is 11 (?) - Zak Seidov zakseidov(AT)yahoo.com

These are the only primes that are the sum of two primes squared. 11=3^2+2 is the only prime of the form p^2+2 because all primes greater than 3 can be written as p=6n-1 or p=6n+1, which allows p^2+2 to be factored. - T. D. Noe, May 18 2007

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

29 belongs to the sequence because it equals 5^2+4.

MATHEMATICA

Select[Prime[ # ]^2+4&/@Range[140], PrimeQ]

CROSSREFS

The corresponding primes p are in A062324.

Cf. A094473-A094479.

Sequence in context: A090866 A098062 A094481 this_sequence A146743 A065546 A075636

Adjacent sequences: A045634 A045635 A045636 this_sequence A045638 A045639 A045640

KEYWORD

nonn,easy

AUTHOR

Felice Russo (felice.russo(AT)katamail.com)

EXTENSIONS

Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Dec 10 2002

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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