The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A100716 Numbers n such that p^p divides n for some prime p. 16
 4, 8, 12, 16, 20, 24, 27, 28, 32, 36, 40, 44, 48, 52, 54, 56, 60, 64, 68, 72, 76, 80, 81, 84, 88, 92, 96, 100, 104, 108, 112, 116, 120, 124, 128, 132, 135, 136, 140, 144, 148, 152, 156, 160, 162, 164, 168, 172, 176, 180, 184, 188, 189, 192, 196, 200, 204, 208, 212 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Complement of A048103; A129251(a(n)) > 0; A051674 is a subsequence; A129254 = (terms a(k) such that a(k+1)=a(k)+1). - Reinhard Zumkeller, Apr 07 2007 A027748(a(n),k) <= A124010(a(n),k) for some k<=A001221(a(n)). - Reinhard Zumkeller, Apr 28 2012 LINKS R. Zumkeller, Table of n, a(n) for n = 1..1000 FORMULA a(n) ~ k*n with k = 1/(1 - prod(1 - p^-p)) = 3.5969959469... where the product is over all primes p. - Charles R Greathouse IV, Jan 24 2012 EXAMPLE 54 is included because 3^3 divides 54. MATHEMATICA fQ[n_] := Union[ Table[ #[[1]] <= #[[2]]] & /@ FactorInteger[n]][[ -1]] == True; Select[ Range[2, 215], fQ[ # ] &] (* Robert G. Wilson v, Dec 14 2004 *) f[n_] := Module[{aux=FactorInteger[n]}, Last@Union@Table[aux[[i, 1]] <=  aux[[i, 2]], {i, Length[aux]}] == True]; Select[Range[2, 215], f] (* José María Grau Ribas, Jan 25 2012 *) Rest@ Select[Range@ 216, Times @@ Boole@ Map[First@ # > Last@ # &, FactorInteger@ #] == 0 &] (* Michael De Vlieger, Aug 19 2016 *) PROG (PARI) is(n)=forprime(p=2, default(primelimit), if(n%p^p==0, return(1)); if(p^p>n, return(0))) \\ Charles R Greathouse IV, Jan 24 2012 (Haskell) a100716 n = a100716_list !! (n-1) a100716_list = filter (\x -> or \$    zipWith (<=) (a027748_row x) (map toInteger \$ a124010_row x)) [1..] -- Reinhard Zumkeller, Apr 28 2012 (Scheme, with Antti Karttunen's IntSeq-library) (define A100716 (NONZERO-POS 1 1 A129251)) ;; Antti Karttunen, Aug 18 2016 CROSSREFS Complement: A048103. Positions of nonzeros in A129251. Cf. A100717, A129150, A129152. Cf. A054744. Cf. A051674 (a subsequence). Subsequence of A276079 from which it differs for the first time at n=175, where a(175) = 628, while A276079(175) = 625, a value missing from here. Sequence in context: A285466 A274141 A086133 * A328251 A276079 A311124 Adjacent sequences:  A100713 A100714 A100715 * A100717 A100718 A100719 KEYWORD nonn AUTHOR Leroy Quet, Dec 10 2004 EXTENSIONS More terms from Robert G. Wilson v, Dec 14 2004 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 8 11:12 EDT 2020. Contains 336293 sequences. (Running on oeis4.)