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A079026 Numbers that can be represented as the sum of twice a prime and three times a prime. 0
10, 12, 13, 15, 16, 19, 20, 21, 23, 25, 27, 28, 29, 31, 32, 35, 37, 39, 40, 41, 43, 44, 45, 47, 49, 52, 53, 55, 57, 59, 61, 63, 64, 65, 67, 68, 71, 73, 75, 77, 79, 80, 83, 85, 88, 89, 91, 92, 93, 95, 97, 99, 101, 103, 107, 109, 112, 113, 115, 117, 119, 121, 124, 125, 127 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

a(n) = 2*p1 + 3*p2, for some primes p1 & p2

EXAMPLE

13 is representable by 2*2 + 3*3, with p1=2 and p2=3

PROG

(PARI) for(i=1, 200, for(j=1, i/2, k=floor((i-2*j)/3); if(i-2*j-3*k, if(isprime(j), if(isprime(k), print(i); break, )))))

CROSSREFS

Sequence in context: A124404 A031288 A127957 * A124867 A199991 A161598

Adjacent sequences:  A079023 A079024 A079025 * A079027 A079028 A079029

KEYWORD

easy,nonn

AUTHOR

Randy L. Ekl (Randy.Ekl(AT)Motorola.com), Feb 01 2003

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Last modified February 16 19:06 EST 2012. Contains 205945 sequences.