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%I #9 Apr 01 2021 22:22:13
%S 3591,4545,5481,6975,8415,9639,11319,11583,11745,12225,12735,16065,
%T 18711,24255,24759,30015,31671,39105,40257,41535,41769,44631,44865,
%U 52065,52569,53055,54975,56511,60255,60705,64071,64575,69825,72009,73665,76095,81081,81855,87129
%N Numbers m such that both m^2-1 and m^2 are refactorable numbers (A033950) and that m^2 has more divisors than m^2-1.
%C Numbers m such that m^2-1 is divisible by d(m^2-1), m^2 is divisible by d(m^2) and d(m^2) > d(m^2-1), d = A000005.
%C The smallest term not divisible by 3 is a(1048) = 2907025.
%H Jianing Song, <a href="/A342970/b342970.txt">Table of n, a(n) for n = 1..1500</a>
%e 5481 is a term since 5481^2-1 is divisible by d(5481^2-1) = 40, 5481^2 is divisible by d(5481^2) = 63, and 63 > 40.
%e 2907025 is a term since 2907025^2-1 is divisible by d(2907025^2-1) = 96, 2907025^2 is divisible by d(2907025^2) = 125, and 125 > 96.
%o (PARI) isA342970(n) = if(n>1, my(d1 = numdiv(n^2-1), d2 = numdiv(n^2)); !((n^2-1) % d1) && !(n^2 % d2) && d2 > d1, 0)
%Y Cf. A000005, A033950, A342969.
%K nonn
%O 1,1
%A _Jianing Song_, Apr 01 2021