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A067048 a(n) = lcm(n, n+1, n+2, n+3, n+4) / 60. 3
1, 1, 7, 14, 42, 42, 462, 66, 429, 1001, 1001, 364, 6188, 1428, 3876, 3876, 6783, 4389, 33649, 3542, 17710, 32890, 26910, 8190, 118755, 23751, 56637, 50344, 79112, 46376, 324632, 31416, 145299, 250971, 191919, 54834, 749398, 141778, 320866, 271502, 407253 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

REFERENCES

Amarnath Murthy, Some Notions on Least Common Multiples, Smarandache Notions Journal, Vol. 12, No. 1-2-3,Spring 2001.

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

FORMULA

From Gary Detlefs Apr 14 2011 and Apr 18 2011: (Start)

a(n) = (n+4)!*gcd(n-1,3)/(360*(n-1)!*gcd(n,4))

a(n) = (n+4)!*(5-4*cos((2*n+1)*Pi/3))/(1080*(n-1)!*(2+(-1)^n+cos(n*Pi/2)))

a(n) = (n+4)!*gcd(n-1,6)/(180*(n-1)!*2^((2*cos(n*Pi/2)+9+(-1)^n)/4)), n>1. (End)

120 <= n*(n+1)*(n+2)*(n+3)*(n+4)/a(n) <= 1440. - Charles R Greathouse IV, Sep 19 2012

EXAMPLE

a(6) = 42 as lcm(6,7,8,9,10)/60 = 2520/60 = 42.

MAPLE

seq(ilcm(n, n+1, n+2, n+3, n+4)/60, n=1..100); # Robert Israel, Feb 07 2016

PROG

(PARI) { for (n=1, 1000, write("b067048.txt", n, " ", lcm(lcm(lcm(n, n+1), lcm(n+2, n+3)), n+4)/60) ) } \\ Harry J. Smith, May 01 2010

CROSSREFS

Cf. A067046, A067047.

Sequence in context: A055780 A161814 A333594 * A189046 A098328 A062098

Adjacent sequences:  A067045 A067046 A067047 * A067049 A067050 A067051

KEYWORD

nonn,easy,less

AUTHOR

Amarnath Murthy, Dec 30 2001

STATUS

approved

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Last modified December 2 03:22 EST 2020. Contains 338865 sequences. (Running on oeis4.)