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A076578 Triangular numbers which are 4-almost primes. 2

%I

%S 36,136,210,276,351,666,820,1035,1225,1275,1326,1431,1770,1830,1953,

%T 2145,2346,2415,2775,2926,3003,3486,3916,4005,4186,4278,5050,5356,

%U 5565,6105,6555,6670,6903,7626,8001,8385,8646,9316,9730,10731,11175,11325

%N Triangular numbers which are 4-almost primes.

%e a(1)=36, 36 is a triangular number and 36=2*2*3*3 i.e. is a product of 4 prime factors so is 4-almost prime.

%K base,easy,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Oct 19 2002

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Last modified August 19 23:59 EDT 2022. Contains 356231 sequences. (Running on oeis4.)