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%I #16 Aug 05 2019 18:20:03
%S 64,95,127,135,143,144,159,160,175,191,192,207,215,216,242,243,272,
%T 279,296,323,335,350,360,368,375,404,405,415,416,431,432,448,455,459,
%U 464,479,485,504,527,528,543,544,559,584,594,615,620,623,647,656,672,719
%N Indices of 7-almost prime triangular numbers.
%H Vincenzo Librandi, <a href="/A240527/b240527.txt">Table of n, a(n) for n = 1..1000</a>
%F { m : A069904(m) = 7 }. - _Alois P. Heinz_, Aug 05 2019
%e a(1) = 64 because A000217(64) = 64*(64+1)/2 = 2080 = 2^5 * 5 * 13 is a 7-almost prime.
%t Flatten[Position[Accumulate[Range[800]],_?(PrimeOmega[#]==7&)]]
%Y Cf. A000217, A069904, A108815, A114435, A114436, A114437, A164977.
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Apr 07 2014
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