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A087916 Number of ordered ways to write 2n+1 as a sum of 3 odd primes. 1
1, 3, 6, 7, 9, 12, 16, 18, 21, 27, 30, 30, 34, 36, 42, 46, 48, 48, 51, 63, 60, 64, 81, 75, 76, 87, 87, 90, 102, 105, 97, 117, 114, 105, 144, 129, 126, 159, 141, 145, 177, 162, 160, 195, 186, 153, 207, 201, 171, 237, 210, 187, 255, 234, 222, 279, 261, 247 (list; graph; refs; listen; history; internal format)
OFFSET

4,2

PROG

(PARI) for(n=1, 100, t=2*n+1:c=0:for(k=1, t, for(l=1, t, for(m=1, t, tt=prime[k]+prime[l]+prime[m]: if(tt>2*n+1, break): if(tt==2*n+1, c=c+1)))):print1(c", "))

CROSSREFS

Cf. A007963 (unordered), A068307 (with 2).

Cf. A087917.

Sequence in context: A026232 A061641 A085359 * A023982 A189092 A191187

Adjacent sequences:  A087913 A087914 A087915 * A087917 A087918 A087919

KEYWORD

nonn,easy

AUTHOR

Ralf Stephan (ralf(AT)ark.in-berlin.de), Oct 18 2003

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Last modified February 15 17:13 EST 2012. Contains 205828 sequences.