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A130714 Number of partitions of n such that every part divides the largest part and such that the smallest part divides every part. 1
1, 2, 3, 5, 6, 10, 11, 16, 19, 26, 27, 41, 42, 55, 64, 81, 83, 114, 116, 151, 168, 202, 210, 277, 289, 348, 382, 460, 478, 604, 623, 747, 812, 942, 1006, 1223, 1269, 1479, 1605, 1870, 1959, 2329, 2434, 2818, 3056, 3458, 3653, 4280, 4493, 5130, 5507, 6231, 6580 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..53.

FORMULA

G.f.: Sum_{i>=0} Sum_(j>0} x^(j+i*j)/Product_{k|i} (1-x^(j*k)).

MAPLE

A130714 := proc(n) local gf, den, i, k, j ; gf := 0 ; for i from 0 to n do for j from 1 to n/(1+i) do den := 1 ; for k in numtheory[divisors](i) do den := den*(1-x^(j*k)) ; od ; gf := taylor(gf+x^(j+i*j)/den, x=0, n+1) ; od ; od: coeftayl(gf, x=0, n) ; end: seq(A130714(n), n=1..60) ; # R. J. Mathar, Oct 28 2007

CROSSREFS

Sequence in context: A018396 A003238 A051839 * A130689 A024560 A000039

Adjacent sequences:  A130711 A130712 A130713 * A130715 A130716 A130717

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Jul 02 2007

EXTENSIONS

More terms from R. J. Mathar, Oct 28 2007

STATUS

approved

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Last modified February 19 20:48 EST 2018. Contains 299357 sequences. (Running on oeis4.)