Ulam numbers: Difference between revisions

=={{header|Ring}}==

<lang ring>

load "stdlib.ring"

limit = 12500

Ulam = []

add(Ulam,1)

add(Ulam,2)

for n = 3 to limit

flag = 0

count = 0

len = len(Ulam)

for x = 1 to len-1

for y = x+1 to len

if Ulam[x] + Ulam[y] = n

flag = 1

count = count + 1

ok

next

next

if flag = 1 and count = 1

add(Ulam,n)

ln = len(Ulam)

if ln = 10

see "The 10th Ulam number is: " + n + nl

ok

if ln = 100

see "The 100th Ulam number is: " + n + nl

ok

if ln = 1000

see "The 1000th Ulam number is: " + n + nl

ok

if ln = 10000

see "The 10000th Ulam number is: " + n + nl

ok

ok

next

</lang>

Output:

<pre>

The 10th Ulam number is: 18

The 100th Ulam number is: 690

The 1000th Ulam number is: 12294

The 10000th Ulam number is: 132788

</pre>