Search: id:A001597 Results 1-1 of 1 results found. %I A001597 M3326 N1336 %S A001597 1,4,8,9,16,25,27,32,36,49,64,81,100,121,125,128,144,169,196,216,225,243, %T A001597 256,289,324,343,361,400,441,484,512,529,576,625,676,729,784,841,900,961, %U A001597 1000,1024,1089,1156,1225,1296,1331,1369,1444,1521,1600,1681,1728,1764 %N A001597 Perfect powers: m^k where m is an integer and k >= 2. %C A001597 Catalan's conjecture (now a theorem) is that 1 occurs just once as a difference, between 8 and 9. %C A001597 Goldbach showed that Sum 1/(a(n)-1) = 1. %D A001597 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %D A001597 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A001597 H. W. Gould, Problem H-170, Fib. Quart., 8 (1970), 268. %D A001597 R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. Addison-Wesley, Reading, MA, 1990, p. 66. %D A001597 D. J. Newman, A Problem Seminar, Springer; see Problem #72. %D A001597 R. Schoof, Catalan's Conjecture, Springer-Verlag, 2008, p. 1. %H A001597 David W. Wilson, Table of n, a(n) for n = 1..10000 %H A001597 A. Dendane, Power (Exponential) Calculator %H A001597 Serhat Sevki Dincer, Powers up to 2^50 %H A001597 Alf van der Poorten, Remarks on the sequence of 'perfect' powers %H A001597 M. Waldschmidt, Open Diophantine problems %H A001597 Eric Weisstein's World of Mathematics, Perfect Power %F A001597 Formulae from postings to the Number Theory List by various authors, 2002: %F A001597 Sum_{i=2}^{infty} sum_{j=2}^{infty} 1/i^j =1; %F A001597 Sum_{k=1}^infty 1/(a_k-1)=1; %F A001597 Sum_{k=1}^infty 1/(a_k+1)= pi^2 / 3 - 5/2; %F A001597 Sum_{k=1}^infty 1/a_k = sum_{n=2}^infty mu(n)(1- zeta(n)) approx = .87446436840494... %F A001597 For asymptotics see Newman. %e A001597 x + 4*x^2 + 8*x^3 + 9*x^4 + 16*x^5 + 25*x^6 + 27*x^7 + 32*x^8 + 36*x^9 + ... %t A001597 Union[ Join[{1}, Flatten[ Table[ n^i, {n, 2, Sqrt[1800]}, {i, 2, Log[n, 1800]}]]]] %t A001597 Join[{1}, Select[Range@1848, GCD @@ Last /@ FactorInteger@# > 1 &]] (* or *) %o A001597 (MAGMA) [1] cat [n : n in [2..1000] | IsPower(n) ]; %o A001597 (PARI) {a(n) = local(m, c); if( n<2, n==1, c=1; m=1; while( c