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 A095842 Prime powers having no partition into two prime powers. 5
 1, 149, 331, 373, 509, 701, 757, 809, 877, 907, 997, 1019, 1087, 1259, 1549, 1597, 1619, 1657, 1759, 1777, 1783, 1867, 1973, 2293, 2377, 2503, 2579, 2683, 2789, 2843, 2879, 2909, 2999, 3119, 3163, 3181, 3187, 3299, 3343, 3433, 3539, 3643 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A095840(A095874(a(n))) = 0. A071330(a(n)) = 0. Here, "prime powers" is used in the relaxed sense, including 1. The numbers 96721, 121801, 192721, 205379, 226981,... seem to be the smallest composite terms of this sequence, which establishes the difference with the subsequence A115231. - M. F. Hasler, Nov 20 2014 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 PROG (PARI) isprimepower(n)=ispower(n, , &n); isprime(n)||n==1; isA095842(n)=if(!isprimepower(n), return(0)); forprime(p=2, n\2, if(isprimepower(n-p), return(0))); forprime(p=2, sqrtint(n\2), for(e=1, log(n\2)\log(p), if(isprimepower(n-p^e), return(0)))); !isprimepower(n-1) \\ Charles R Greathouse IV, Jul 06 2011 (Haskell) a095842 n = a095842_list !! (n-1) a095842_list = filter ((== 0) . a071330) a000961_list -- Reinhard Zumkeller, Jan 11 2013 CROSSREFS Subsequence of A071331. Cf. A000961, A095841. Sequence in context: A244661 A146137 A071331 * A142359 A185692 A216312 Adjacent sequences:  A095839 A095840 A095841 * A095843 A095844 A095845 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jun 10 2004 STATUS approved

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Last modified June 26 20:19 EDT 2019. Contains 324380 sequences. (Running on oeis4.)