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A112022
Number of partitions of n into distinct Chen primes.
5
1, 0, 1, 1, 0, 2, 0, 2, 1, 1, 2, 1, 2, 2, 2, 2, 3, 2, 4, 3, 4, 4, 4, 5, 5, 5, 6, 5, 6, 7, 6, 9, 7, 9, 9, 9, 11, 11, 11, 13, 12, 14, 15, 14, 17, 15, 17, 19, 18, 21, 21, 21, 24, 24, 26, 28, 27, 30, 30, 32, 35, 34, 37, 37, 39, 41, 43, 45, 46, 48, 51, 53, 56, 58, 59, 61, 64, 66, 70, 71, 73
OFFSET
0,6
COMMENTS
a(n) = A000586(n) for n <= 42.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 0..10000
FORMULA
G.f.: Product_{k>=1} (1 + x^A109611(k)). - Andrew Howroyd, Dec 28 2017
MATHEMATICA
terms = 81;
gf = Times @@ (1 + x^SequencePosition[ PrimeOmega[ Range[terms]], {1, _, 1|2}][[All, 1]]) + O[x]^terms;
CoefficientList[gf, x] (* Jean-François Alcover, Jul 02 2018 *)
PROG
(PARI) P=1+O(x^1001); forprime(p=2, 1e3, if(bigomega(p+2)<3, P*=1+x^p)); Vec(P) \\ Charles R Greathouse IV, May 13 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 26 2005
STATUS
approved