login
A111484
Triangular numbers all of whose digits are nonprimes.
0
0, 1, 6, 10, 66, 91, 190, 406, 496, 666, 861, 946, 990, 1081, 1891, 4186, 6441, 8001, 8646, 8911, 9180, 10011, 10440, 14196, 16110, 19110, 19900, 40186, 41041, 41616, 49141, 64980, 66066, 69006, 80601, 81406, 81810, 84666, 88410, 90100, 91806
OFFSET
1,3
PROG
(Perl) my $n = 0, $t = 0, $i = 0;
for (; $n < 6293912; $n++, $t += $n) {
if ($t =~ m/^[014689]+$/) {
$i++;
print("$i $t\n");
}
} # Charles R Greathouse IV, Dec 17 2010
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jonathan Vos Post, Nov 15 2005
STATUS
approved