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A103263 Number of partitions of n into distinct parts prime to 3 and 5. 1
1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 5, 5, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 17, 18, 20, 22, 25, 28, 30, 33, 36, 39, 43, 48, 52, 56, 61, 67, 73, 80, 87, 94, 101, 110, 120, 130, 141, 152, 164, 177, 192, 207, 223, 240, 258, 278, 301, 324, 348, 373, 400, 429, 461, 496 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..67.

FORMULA

Expansion of q^(-1/3)(eta(q^2)*eta(q^3)*eta(q^5)*eta(q^30))/(eta(q)*eta(q^6)*eta(q^10)*eta(q^15)) in powers of q. - Michael Somos, Sep 22 2005.

G.f.: product_{k>0}((1+x^k)*(1+x^(15k)))/((1+x^(3k))*(1+x^(5k))).

Euler transform of period 30 sequence [1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, ...]. - Michael Somos, Sep 22 2005

Given g.f. A(x), then B(x)=x*A(x^3) satisfies 0=f(B(x), B(x^2)) where f(u, v)=u*(u-v^2)^2 +v*(v-u^2)^2 -u*v -(u*v)^3. - Michael Somos, Sep 22 2005

Given g.f. A(x), then B(x)=x*A(x^3) satisfies 0=f(B(x), B(x^2), B(x^4)) where f(u, v, w)=(v+u*w)^2 -v*(u^2+w^2). - Michael Somos, Sep 22 2005

G.f.: Product_{k>0} (1+x^k-x^(3k)-x^(4k)-x^(5k)+x^(7k)+x^(8k)). - Michael Somos Sep 22 2005

a(n) ~ exp(2*Pi*sqrt(2*n/5)/3) / (2^(3/4) * sqrt(3) * 5^(1/4) * n^(3/4)). - Vaclav Kotesovec, Sep 06 2015

EXAMPLE

E.g. a(15)=5 because we can write 15 as 14+1=13+2=11+4=8+7=8+4+2+1.

MAPLE

series(product((1+x^k)*(1+x^(15*k))/((1+x^(3*k))*(1+x^(5*k))), k=1..100), x=0, 100);

MATHEMATICA

CoefficientList[ Series[ Product[(1 + x^k)(1 + x^(15*k))/((1 + x^(3k))*(1 + x^(5k))), {k, 100}], {x, 0, 75}], x] (* Robert G. Wilson v, Feb 22 2005 *)

PROG

(PARI) {a(n)=local(A); if (n<0, 0, A=x*O(x^n); polcoeff( eta(x^2+A)*eta(x^3+A)*eta(x^5+A)*eta(x^30+A)/ (eta(x+A)*eta(x^6+A)*eta(x^10+A)*eta(x^15+A)), n))} /* Michael Somos, Sep 22 2005 */

CROSSREFS

Sequence in context: A261796 A200245 A116492 * A173777 A140436 A236916

Adjacent sequences:  A103260 A103261 A103262 * A103264 A103265 A103266

KEYWORD

easy,nonn

AUTHOR

Noureddine Chair, Feb 21 2005

EXTENSIONS

More terms from Robert G. Wilson v, Feb 22 2005

STATUS

approved

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Last modified April 15 06:12 EDT 2021. Contains 342975 sequences. (Running on oeis4.)