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A185061
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Position of the first occurrence of n in A193358 when it is considered to have the starting offset 1 instead of 0.
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0
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1, 2, 5, 3, 11, 7, 19, 13, 29, 21, 41, 31, 55, 43, 71, 57, 89, 73, 109, 91, 131, 111, 155, 133, 181, 157, 209, 183, 239, 211, 271, 241, 305, 273, 341, 307, 379, 343, 419, 381, 461, 421, 505, 463, 551, 507, 599, 553, 649, 601, 701, 651, 755, 703, 811, 757
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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G.f.: x*(x^6 - x^5 - 3*x^4 + 4*x^3 - x^2 - x - 1)/((x - 1)^3*(x + 1)^2).
a(2*n) = n*(n-1) + 1 for n > 1.
a(2*n+1) = n*(n+3) + 1.
a(n) = a(n-1) + 2*a(n-2) - 2*a(n-3) - a(n-4) + a(n-5) for n > 7. (End)
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MATHEMATICA
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aux[0]=1; aux[1]=2; aux[n_]:=aux[n]=aux[n-aux[n-2]]+2;
a[i_]:={n=0; While[!(aux[n]==i), n++]; n};
Flatten[Table[a[i]+1, {i, 1, 100}]]
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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