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A000135 Number of partitions into non-integral powers.
(Formerly M1595 N0622)
1
1, 2, 6, 13, 24, 42, 73, 125, 204, 324, 511, 801, 1228, 1856, 2780, 4135, 6084, 8873, 12847, 18481, 26416, 37473, 52871, 74216, 103596, 143841, 198839, 273654, 374987, 511735, 695559, 941932, 1271139, 1709474, 2291195, 3061385, 4078152, 5416322 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

a(n) counts the solutions to the inequality sum_{i=1,2,..} x_i^(2/3)<=n for any number of distinct integers 1<=x_1<x_2<x_3<x_4<... - R. J. Mathar, Jul 03 2009

REFERENCES

B. K. Agarwala and F. C. Auluck, Statistical mechanics and partitions into non-integral powers of integers, Proc. Camb. Phil. Soc., 47 (1951), 207-216.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

B. K. Agarwala, F. C. Auluck, Statistical mechanics and partitions into non-integral powers of integers, Proc. Camb. Phil. Soc., 47 (1951), 207-216.

Sean A. Irvine, Tentative values of first 55 terms

EXAMPLE

For n=3, the 6 solutions are (i) 1^(2/3)<=3. (ii) 1^(2/3)+2^(2/3)<=3. (iii) 2^(2/3)<=3. (iv) 3^(2/3)<=3. (v) 4^(2/3)<=3. (vi) 5^(2/3)<=3. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 03 2009]

CROSSREFS

Cf. A000148, A000158, A000160.

Sequence in context: A184533 A178532 A003600 * A065220 A048094 A181522

Adjacent sequences:  A000132 A000133 A000134 * A000136 A000137 A000138

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

8 more terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 03 2009

20 more terms from Sean A. Irvine (sairvin(AT)xtra.co.nz), Sep 28 2009

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.