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A070215 Number of ways to write the n-th prime as a sum of distinct primes. 5
1, 1, 2, 2, 1, 2, 2, 3, 5, 7, 9, 11, 14, 15, 19, 26, 35, 39, 50, 61, 67, 87, 102, 130, 178, 204, 224, 257, 278, 320, 522, 595, 724, 776, 1064, 1136, 1364, 1634, 1836, 2192, 2601, 2761, 3645, 3863, 4294, 4549, 6262, 8558, 9453, 9964, 11001, 12774, 13438 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Seth Troisi, Table of n, a(n) for n = 1..1201

FORMULA

a(n) = A000586(A000040(n)). - R. J. Mathar, Apr 30 2007

EXAMPLE

With the 10th prime 29, for instance, we have a(10)=7 distinct-prime partitions, viz. 29 = 2 + 3 + 7 + 17 = 2 + 3 + 5 + 19 = 2 + 3 + 11 + 13 = 3 + 7 + 19 = 5 + 7 + 17 = 5 + 11 + 13.

MATHEMATICA

nn = PrimePi[300]; t = CoefficientList[Series[Product[(1 + x^Prime[k]), {k, nn}], {x, 0, Prime[nn]}], x]; t[[1 + Prime[Range[nn]]]] (* T. D. Noe, Nov 13 2013 *)

PROG

(Haskell)

a070215 = a000586 . a000040  -- Reinhard Zumkeller, Aug 05 2012

CROSSREFS

Cf. A000586.

Sequence in context: A112175 A112206 A038541 * A071457 A227782 A255771

Adjacent sequences:  A070212 A070213 A070214 * A070216 A070217 A070218

KEYWORD

nonn

AUTHOR

Lekraj Beedassy, May 07 2002

EXTENSIONS

More terms from Naohiro Nomoto and Don Reble (djr(AT)nk.ca), May 11 2002

Offset in b-file corrected by N. J. A. Sloane, Aug 31 2009

STATUS

approved

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Last modified June 24 07:19 EDT 2017. Contains 288697 sequences.