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a(n) is the smallest composite number having the same base-n digits (both type and quantity) as the primes and greater-than-one exponents in its factorization.
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%I #5 Jan 20 2017 20:01:23

%S 25,16,25,2312,16,7136,27,72646,25,4617,169,384,4119,3875,289,182585,

%T 128,556875,451,49,529,1012985,679,72420352,42752,585903,841,64,961,

%U 118375,1285,2944,179503,4624625,1369

%N a(n) is the smallest composite number having the same base-n digits (both type and quantity) as the primes and greater-than-one exponents in its factorization.

%e In base 2: The digits of 25 (11001) are the same type and quantity as the total of the prime 5 (101) and its exponent 2 (10) in 25's factorization; 2 zeros, 3 ones.

%e In base 26: The digits of 42752 (2,11,6,8) are the same type and quantity as the total of the prime 2 (2) and its exponent 8 (8) and the prime 167 (6,11) in 42752's factorization; 1 each of two, six, eight, eleven.

%Y Cf. A273260, A281336.

%K nonn,base

%O 2,1

%A _Hans Havermann_, Jan 20 2017