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A241787
Triangular numbers which have one or more occurrences of exactly four different digits.
7
1035, 1275, 1326, 1378, 1485, 1540, 1596, 1653, 1830, 1953, 2016, 2145, 2346, 2415, 2485, 2701, 2850, 3081, 3160, 3240, 3486, 3570, 3741, 3916, 4095, 4186, 4278, 4371, 4560, 4753, 4851, 4950, 5460, 5671, 6105, 6328, 6903, 7021, 7140, 7260, 7381, 7503, 8256
OFFSET
1,1
COMMENTS
The first term having a repeated digit is 10153.
LINKS
MATHEMATICA
Select[Accumulate[Range[200]], Count[DigitCount[#], 0]==6&] (* Harvey P. Dale, Jun 29 2022 *)
PROG
(PARI) s=[]; for(n=0, 300, if(#vecsort(eval(Vec(Str(n*(n+1)/2))), , 8)==4, s=concat(s, n*(n+1)/2))); s
KEYWORD
nonn,base
AUTHOR
Colin Barker, Apr 28 2014
STATUS
approved