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A090283
"Plain Bob Minimus" in bell-ringing is a sequence of permutations p_1=(1,2,3,4), p_2=(2,1,4,3), .. which runs through all permutations of {1,2,3,4} with period 24; sequence gives position of bell 3 in n-th permutation.
2
3, 4, 4, 3, 2, 1, 1, 2, 2, 1, 1, 2, 3, 4, 4, 3, 4, 3, 2, 1, 1, 2, 3, 4, 3, 4, 4, 3, 2, 1, 1, 2, 2, 1, 1, 2, 3, 4, 4, 3, 4, 3, 2, 1, 1, 2, 3, 4, 3, 4, 4, 3, 2, 1, 1, 2, 2, 1, 1, 2, 3, 4, 4, 3, 4, 3, 2, 1, 1, 2, 3, 4, 3, 4, 4, 3, 2, 1, 1, 2, 2, 1, 1, 2, 3, 4, 4, 3, 4, 3, 2, 1, 1, 2, 3, 4, 3, 4, 4
OFFSET
1,1
FORMULA
Period 24.
From Chai Wah Wu, Jul 17 2016: (Start)
a(n) = a(n-1) - a(n-4) + a(n-5) - a(n-8) + a(n-9) - a(n-12) + a(n-13) - a(n-16) + a(n-17) - a(n-20) + a(n-21) for n > 21.
G.f.: x*(-4*x^20 + x^19 + x^18 + x^17 - 4*x^16 - 3*x^12 - x^11 + x^9 - 2*x^8 - 2*x^4 + x^3 - x - 3)/((x - 1)*(x^4 + 1)*(x^2 - x + 1)*(x^2 + x + 1)*(x^4 - x^2 + 1)*(x^8 - x^4 + 1)). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 24 2004
STATUS
approved