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Numbers n which when expressed in base 16 are palindromes whose digit sum and digit product both divide n.
2

%I #8 Sep 01 2014 01:34:46

%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,273,69905,78129,200979,17903889,

%T 4581298449,1172816597265,1174959919377,300240008712465,

%U 300240176484625,370608786444625

%N Numbers n which when expressed in base 16 are palindromes whose digit sum and digit product both divide n.

%o (Python)

%o from operator import mul

%o from functools import reduce

%o from gmpy2 import t_mod, digits, mpz

%o A246337 = sorted([mpz(n,16) for n in (digits(x,16)+digits(x,16)[::-1]

%o ....for x in range(1,16**7)) if not (n.count('0') or

%o ....t_mod(mpz(n,16), sum((mpz(d,16) for d in n)))

%o ....or t_mod(mpz(n,16), reduce(mul,(mpz(d,16) for d in n))))] +

%o ....[mpz(n,16) for n in (digits(x,16)+digits(x,16)[-2::-1]

%o ....for x in range(16**7)) if not (n.count('0') or

%o ....t_mod(mpz(n,16), sum((mpz(d,16) for d in n)))

%o ....or t_mod(mpz(n,16), reduce(mul,(mpz(d,16) for d in n))))])

%Y Cf. A117228, A246338.

%K nonn,base

%O 1,2

%A _Chai Wah Wu_, Aug 22 2014