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A117512 Triangular numbers for which the sum of the digits is a prime number. 0
3, 21, 120, 210, 300, 496, 595, 946, 1378, 1891, 2278, 2485, 2926, 3655, 3916, 4186, 4465, 4753, 5356, 5671, 6328, 6670, 7381, 7750, 8128, 8515, 8911, 9316, 9730, 10011, 10585, 11476, 11935, 12880, 13366, 13861, 14365, 15931, 16471, 18145, 18721 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

595 is in the sequence because (1) it is a triangular number and (2) the sum of its digits 5+9+5=19 is a prime number.

MATHEMATICA

With[{trnos=Accumulate[Range[200]]}, Select[trnos, PrimeQ[Total[IntegerDigits[#]]]&]]  (* From Harvey P. Dale, Feb 14 2011 *)

CROSSREFS

Cf. A000217.

Sequence in context: A178537 A046727 A084159 * A068127 A171137 A144884

Adjacent sequences:  A117509 A117510 A117511 * A117513 A117514 A117515

KEYWORD

nonn,base

AUTHOR

Luc Stevens (lms022(AT)yahoo.com), Apr 26 2006

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Last modified February 17 16:39 EST 2012. Contains 206058 sequences.