cp's OEIS Frontend

A372294 The smallest number k which, when written in base n, has a factorization k = f_1*f_2*...*f_r where f_i >= 1 and the digits of {k, f_1, f_2, ..., f_r} together contain the digits 0,1,...,(n-1) exactly once. Set a(n) = -1 if no such k exists.

%I A372294 #7 Apr 28 2024 11:56:23
%S A372294 -1,-1,-1,-1,-1,104,440,1440,4830,15552,72240,282240,1039104,4244940,
%T A372294 24108000
%N A372294 The smallest number k which, when written in base n, has a factorization k = f_1*f_2*...*f_r where f_i >= 1 and the digits of {k, f_1, f_2, ..., f_r} together contain the digits 0,1,...,(n-1) exactly once. Set a(n) = -1 if no such k exists.
%C A372294 Similar to A372249, except that here the factors are allowed to be equal to 1. Differs from A372249 at n = 7, 10, 12, 15, ...
%F A372294 a(n) <= A372249(n).
%e A372294 a(7)  =      104 = 1*4*26
%e A372294 a(8)  =      440 = 2*4*5*11
%e A372294 a(9)  =     1440 = 3*4*5*24
%e A372294 a(10) =     4830 = 1*2*5*7*69
%e A372294 a(11) =    15552 = 2*3*6*8*54
%e A372294 a(12) =    72240 = 1*4*6*7*430
%e A372294 a(13) =   282240 = 2*3*5*7*21*64
%e A372294 a(14) =  1039104 = 2*3*4*6*8*11*82
%e A372294 a(15) =  4244940 = 1*2*3*7*9*10*1123
%e A372294 a(16) = 24108000 = 3*4*5*7*10*41*140
%Y A372294 Cf. A372249, A372053, A370970, A371958.
%K A372294 sign,base,more
%O A372294 2,6
%A A372294 _Chai Wah Wu_, Apr 25 2024