OFFSET
1,2
EXAMPLE
8 is the smallest exponent such that 3^8 contains two consecutive increasing integers (3^8 = 6561).
20 is the smallest exponent such that 3^20 contains three consecutive increasing integers (3^20 = 3486784401).
PROG
(Python)
def StrInc(x):
..for n in range(10**5):
....count = 0
....i = 0
....string = str(3**n)
....if len(string) == x and x == 1:
......return n
....while i < len(string)-1:
......if int(string[i]) == int(string[i+1])-1:
........count += 1
........i += 1
......else:
........if count >= x-1:
..........return n
........else:
..........count = 0
..........i += 1
....if count >= x-1:
......return n
x = 1
while x < 15:
..print(StrInc(x))
..x += 1
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
Derek Orr, Feb 27 2014
EXTENSIONS
a(8)-a(10) from Giovanni Resta, Mar 02 2014
STATUS
approved