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A068132
Triangular numbers with sum of digits = 28.
1
5995, 14878, 17578, 24976, 29890, 32896, 36856, 37675, 42778, 47278, 52975, 53956, 54946, 55945, 56953, 57970, 67528, 68635, 69751, 70876, 75466, 76636, 77815, 83845, 85078, 87571, 88831, 91378, 92665, 93961, 95266, 96580, 97903
OFFSET
1,1
COMMENTS
The sequence is unbounded, as the (10^k + 9)-th triangular number for k>1 is a term.
The sum of the digits of triangular numbers in most cases is a triangular number.
Conjecture: For every triangular number T there exist infinitely many triangular numbers with sum of digits = T.
MATHEMATICA
Select[Accumulate[Range[500]], Total[IntegerDigits[#]]==28&] (* Harvey P. Dale, Aug 30 2015 *)
CROSSREFS
Subsequence of A000217.
Sequence in context: A055108 A046903 A171351 * A250514 A343432 A115429
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Feb 21 2002
EXTENSIONS
More terms from Sascha Kurz, Mar 06 2002
Offset changed by Andrew Howroyd, Sep 19 2024
STATUS
approved