

A145011


First differences of A007775.


3



6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2, 6, 4, 2, 4, 2, 4, 6, 2
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OFFSET

1,1


COMMENTS

Terms of the simple continued fraction of 3836/[sqrt(19822530)3836].  Paolo P. Lava, Aug 05 2009
Also the first differences of A084968 divided by 7.  Antti Karttunen, May 01 2015


LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000


FORMULA

Period 8: repeat 6,4,2,4,2,4,6,2.
a(n) = (1/112)*{41*(n mod 8)+71*[(n+1) mod 8]13*[(n+2) mod 8]13*[(n+3) mod 8]+43*[(n+4) mod 8]13*[(n+5) mod 8]+43*[(n+6) mod 8]+43*[(n+7) mod 8]}, with n>=0. [Paolo P. Lava, Aug 28 2009]
a(n) = 2*((abs(abs((n mod 8)  3)  1) mod 3) + 1).  Pieter Stadhouders, Mar 09 2010


MATHEMATICA

Differences[Select[Range[400], GCD[#, 30]==1&]] (* Harvey P. Dale, Dec 07 2011 *)


PROG

(Haskell)
a145011 n = a145011_list !! (n1)
a145011_list = zipWith () (tail a007775_list) a007775_list
 Reinhard Zumkeller, Jan 06 2013
(PARI) a(n)=[4, 6, 4, 2, 4, 2][n%8+1] \\ Charles R Greathouse IV, Oct 20 2013


CROSSREFS

Cf. A007775, A084968.
Multiplied by 7: row 4 of A257251.
Sequence in context: A125214 A114062 A028975 * A173625 A086036 A019849
Adjacent sequences: A145008 A145009 A145010 * A145012 A145013 A145014


KEYWORD

nonn,easy


AUTHOR

Ki Punches, Feb 25 2009


EXTENSIONS

Edited by Omar E. Pol, Mar 02 2009
Offset corrected by Reinhard Zumkeller, Jan 06 2013


STATUS

approved



