Source code in the basic256 programming language

function digit_sum(n, sum)
	# devuelve la suma de los dígitos de n dada la suma de los dígitos de n - 1
	sum ++
	while (n > 0 and n mod 10 = 0)
		sum -= 9
		n = int(n / 10)
	end while
	return sum
end function

function divisible(n, d)
	if ((d mod 1) = 0) and ((n mod 1) = 1) then
		return 0
	end if
	return (n mod d = 0)
end function

global sum
sum = 0
gap = 0 : niven = 0 : niven_index = 0
gap_index = 0
previous  = 1
print "Gap index    Gap      Niven index     Niven number"
print "---------    ---      -----------     ------------"

for niven = 1 to 1000000
	sum = digit_sum(niven, sum)
	if divisible(niven, sum) then
		if (niven > previous + gap) then
			gap_index += 1
			gap = niven - previous
			print gap_index, gap, niven_index, previous
		end if
		previous = niven
		niven_index ++
	end if
next niven
end