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%I #22 Sep 28 2014 12:13:24
%S 2,3,5,13,17,73,97,193,257,769,3457,7681,15361,12289,40961,114689,
%T 65537,737281,1376257,786433,5308417,7340033,14155777,28311553,
%U 104857601,113246209,167772161,469762049,2113929217,1811939329
%N Smallest prime p with bigomega(p-1)=n, where bigomega(m)=A001222(m) is the number of prime divisors of m (counted with multiplicity).
%H David W. Wilson and Robert G. Wilson v, <a href="/A073919/b073919.txt">Table of n, a(n) for n = 0..351</a>
%e a(2) = 5 = 2*2 + 1. a(5) = 73 = 2*2*2*3*3 + 1.
%t ptns[n_, 0] := If[n==0, {{}}, {}]; ptns[n_, k_] := Module[{r}, If[n<k, Return[{}]]; ptns[n, k]=1+Union@@Table[PadRight[ #, k]&/@ptns[n-k, r], {r, 0, k}]]; a[n_] := Module[{i, l, v}, v=Infinity; For[i=n, True, i++, l=(Times@@Prime/@#&)/@ptns[i, n]; If[Min@@l>v, Return[v]]; minp=Min@@Select[l+1, ProvablePrimeQ]; If[minp<v, v=minp]]] (* First do <<NumberTheory`PrimeQ`. ptns[n, k] is list of partitions of n into exactly k parts *) Array[a, 30, 0]
%t With[{x=Table[{Prime[n],PrimeOmega[Prime[n]-1]},{n,104000000}]},Transpose[ Table[ SelectFirst[x,#[[2]]==i&],{i,0,29}]][[1]]] (* _Harvey P. Dale_, Sep 28 2014 *)
%Y Cf. A118883.
%K nonn
%O 0,1
%A _Amarnath Murthy_, Aug 18 2002
%E Edited by _Dean Hickerson_, Nov 12 2002
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