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A320601
Exponents of powers of two having a digit zero in decimal.
1
10, 11, 12, 17, 20, 21, 22, 23, 26, 29, 30, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 68, 69, 70, 71, 73, 74, 75, 78, 79, 80, 82, 83, 84, 85, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105
OFFSET
1,1
COMMENTS
Complement of A007377. It is a long-standing open problem to show that this sequence contains all numbers > 86.
FORMULA
{ n | A027870(n) > 0}, where A027870 = A055641 o A000079.
EXAMPLE
The first term is a(1) = 10 since 2^10 = 1024 is the smallest power of 2 having a digit 0.
PROG
(PARI) for(n=1, 199, vecmin(digits(2^n))||print1(n", "))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Oct 16 2018
STATUS
approved