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A051030 Ramanujan's c-series. 3
2, 172, 14258, 1183258, 98196140, 8149096378, 676276803218, 56122825570732, 4657518245567522, 386517891556533610, 32076327480946722092, 2661948663027021400042, 220909662703761829481378 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

The "amazing" identity of Ramanujan is a(n)^3 + b(n)^3 = c(n)^3 + (-1)^n, where a(n)=A051028(n), b(n)=A051029(n) and c(n)=A051030(n). - Emeric Deutsch (deutsch(AT)duke.poly.edu), Oct 14 2006

REFERENCES

M. D. Hirschhorn, A Proof in the Spirit of Zeilberger of an Amazing Identity of Ramanujan.

Jung Hun Han and Michael D. Hirschhorn, Another look at an amazing identity of Ramanujan, Math. Magazine, 79, No. 2, 2006, 302-304.

LINKS

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

FORMULA

G.f.: f(x)=(2+8x-10x^2)/(1-82x-82x^2+x^3).

X(n+1)=AX(n), where X(n)=transpose(A051028(n), A051029(n), A051030(n)) and A = matrix (3,3,[63,104,-68; 64,104,-67; 80,131,-85)]). - Emeric Deutsch (deutsch(AT)duke.poly.edu), Oct 14 2006

MAPLE

g:=(2+8*x-10*x^2)/(1-82*x-82*x^2+x^3): gser:=series(g, x=0, 20): seq(coeff(gser, x, n), n=0..12); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Oct 14 2006

CROSSREFS

Cf. A051028, A051029.

Sequence in context: A005020 A157316 A007760 * A139935 A172231 A193638

Adjacent sequences:  A051027 A051028 A051029 * A051031 A051032 A051033

KEYWORD

nonn

AUTHOR

Eric Weisstein (eric(AT)weisstein.com)

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Last modified February 15 18:22 EST 2012. Contains 205835 sequences.