

A233933


Smallest number k such that R(n) is the nth divisor of k, where R(n) is the nth Ramanujan prime (A104272).


0



11, 34, 116, 246, 752, 708, 4288, 1704, 3492, 4848, 11556, 7620, 28608, 47112, 24048, 21480, 45612, 40860, 54960, 218088, 180684, 121464, 94680, 242100, 269760, 486288, 313488, 249840, 376920, 308280, 738540, 721800, 515340, 1106160, 930960, 935280, 737520
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OFFSET

2,1


LINKS

Table of n, a(n) for n=2..38.


EXAMPLE

a(2) = 11 because the divisors of 11 are {1, 11}, and the 2nd divisor of 11 is 11 = A104272(2);
a(3) = 34 because the divisors of 34 are {1, 2, 17, 34}, and the 3rd divisor of 34 is 17 = A104272(3).


MATHEMATICA

nn=20; R=Table[0, {nn}]; s=0; Do[If[PrimeQ[k], s++]; If[PrimeQ[k/2], s]; If[s<nn, R[[s+1]]=k], {k, Prime[3*nn]}]; R=R+1; t=Table[0, {nn}]; found=1; n=2; While[found < nn, n++; d=Divisors[n]; Do[If[i <= nn && d[[i]] == Part[R, i] && t[[i]]==0, t[[i]]=n; found++], {i, Length[d]}]]; Rest[t] (* Program from T. D. Noe adapted for this sequence  see A104272 and A221647 *)


CROSSREFS

Cf. A104272, A221647.
Sequence in context: A103661 A300418 A041539 * A041232 A050287 A096762
Adjacent sequences: A233930 A233931 A233932 * A233934 A233935 A233936


KEYWORD

nonn


AUTHOR

Michel Lagneau, Dec 18 2013


STATUS

approved



