A341032 Numbers k such that A124440(k) is a square.
1, 2, 10, 17, 469, 646, 1542, 1601, 24939, 25090, 43690, 50925, 77577, 84002, 131087, 156817, 174755, 182106, 220974, 293930, 371307, 389130, 394290, 401573, 440819, 492886, 584326, 609301, 839590, 935685, 1727207, 1775622, 1939666, 1948705, 2235041, 2267650
Offset: 1
Keywords
Examples
a(4) = 17 is a term because A124440(17) = 100 = 10^2.
Links
- Daniel Suteu, Table of n, a(n) for n = 1..100
Programs
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Maple
N:= 40000: # for terms <= N G:= add(numtheory:-mobius(n)*n*x^(2*n)/((1-x^n)*(1-x^(2*n))^2), n=1..N/2): S:= series(G, x, N+1): A66840:= [seq(coeff(S, x, j), j=1..N)]: f:= proc(n) n*numtheory:-phi(n)/2 - A66840[n] end proc: f(1):= 1: f(2):= 1: select(t -> issqr(f(t)), [$1..N]);
Extensions
More terms from Daniel Suteu, Feb 03 2021
Comments