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A154633 (4n+1)(4n+3)(4n+5)(4n+7) 2
105, 3465, 19305, 62985, 156009, 326025, 606825, 1038345, 1666665, 2544009, 3728745, 5285385, 7284585, 9803145, 12924009, 16736265, 21335145, 26822025, 33304425, 40896009, 49716585, 59892105, 71554665, 84842505, 99900009 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Sum_{n>=0} 1/a(n) = (3Pi-8)/144

3 divides a(n).

FORMULA

G.f.: 3*(35+980*x+1010*x^2+20*x^3+3*x^4)/(1-x)^5

a(n)=(4n+1)(4n+3)(4n+5)(4n+7)

a(n)=5a(n-1)-10a(n-2)+10a(n-3)-5a(n-4)+a(n-5)

CROSSREFS

Cf. A133766, A001539, A157142.

Sequence in context: A112497 A166821 A166803 * A122814 A112490 A006361

Adjacent sequences:  A154630 A154631 A154632 * A154634 A154635 A154636

KEYWORD

easy,nonn

AUTHOR

Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Jan 13 2009

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Last modified February 17 09:17 EST 2012. Contains 206009 sequences.