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A146892
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For definition see comments lines.
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3
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1, 6, 6, 72, 72, 72, 6, 72, 72, 5184, 6, 5184, 72, 5184, 31104, 5184, 5184, 5184, 2592, 5184, 432, 373248, 36, 373248, 31104, 26873856, 26873856, 26873856, 373248, 31104, 36, 31104, 2239488, 2239488, 1934917632, 26873856, 31104, 2239488
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OFFSET
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0,2
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COMMENTS
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Let USigma denote the unitary sigma function, A034448.
As in A146891, let PF_p(n) denote the largest power of the prime p dividing n. PF_2 is A006519, and PF_3 is A038500. Furthermore define PF_1(n)=1.
Extension to multi-prime-indices is done by multiplying the corresponding functions: PF_{p,q,..}(n) = PF_p(n)*PF_q(n)*... An example of this is PF_{2,3} = A065331.
[How to compute c(m)]
Case of Base Primes = {2}{3}
c(0)=2^m, b(0)=2^m
c(n)=c(n-1)/PF_2[USigma[b(n-1)]]*PF_3[USigma[b(n-1)]]
b(n)=USigma[b(n-1)]/ PF_2,3[USigma[b(n-1)]]
IF b(k)=1 THEN END
a(m)=c(k)
Sequence gives a(m)
Factorization of term becomes 2^r*3^s.
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LINKS
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Table of n, a(n) for n=0..37.
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MAPLE
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A146892 := proc(n) local b, a, k ;
b := [2^n] ;
while op(-1, b) <> 1 do
b := [op(b), A065330(A034448(op(-1, b))) ] ;
od:
a := 2^n ;
for k from 2 to nops(b) do
a := a/ A006519(A034448(op(k-1, b))) *A038500(A034448(op(k-1, b))) ;
od:
a ;
end: # R. J. Mathar, Jun 24 2009
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CROSSREFS
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Cf. A146891.
Sequence in context: A269888 A269767 A065239 * A320824 A085804 A012125
Adjacent sequences: A146889 A146890 A146891 * A146893 A146894 A146895
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KEYWORD
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nonn,uned
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AUTHOR
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Yasutoshi Kohmoto, Apr 17 2009
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EXTENSIONS
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More terms from R. J. Mathar, Jun 24 2009
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STATUS
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approved
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