%I #22 Nov 17 2020 08:52:57
%S 0,1,5,11,19,28,38,50,64,79,95,113,133,154,176,200,225,251,278,306,
%T 336,368,401,435,470,506,544,583,623,665,709,754,800,848,897,947,998,
%U 1050,1104,1159,1215,1272,1330,1390,1452,1515,1579,1644,1710,1778,1847,1917
%N Sum of first n nonprimes.
%C Partial sums of A141468 or A018252. - _R. J. Mathar_, Mar 01 2009
%C The lexicographically earliest sequence with first differences as increasing sequence of composites A002808. Complement of A175970. See A175965, A175966, A175967, A014284, A175969, A175970. - _Jaroslav Krizek_, Oct 31 2010
%H Nathaniel Johnston, <a href="/A051349/b051349.txt">Table of n, a(n) for n = 0..10000</a>
%F Sum_{n>=1} 1/a(n) = A122998. - _Amiram Eldar_, Nov 17 2020
%p ithnonprime := proc(n)local k: option remember: if(n=1)then return 1: fi: for k from procname(n-1)+1 do if(not isprime(k))then return k fi: od: end: A051349 := proc(n) option remember: local k: if(n<=1)then return n: fi: return ithnonprime(n)+procname(n-1): end: seq(A051349(n),n=0..51); # _Nathaniel Johnston_, May 25 2011
%t lst={};s=0;Do[If[ !PrimeQ[n], s=s+n;AppendTo[lst, s]], {n, 0, 10^2}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 14 2008 *)
%Y Cf. A014284, A018252, A122998, A141468, A175965, A175966, A175967, A175969, A175970.
%K nonn,easy
%O 0,3
%A Armand Turpel (armandt(AT)unforgettable.com)
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