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%I A048395
%S A048395 0,5,26,75,164,305,510,791,1160,1629,2210,2915,3756,4745,5894,7215,
%T A048395 8720,10421,12330,14459,16820,19425,22286,25415,28824,32525,36530,
%U A048395 40851,45500,50489,55830,61535,67616,74085,80954,88235,95940,104081
%N A048395 Sum of consecutive nonsquares.
%C A048395 Relationship with natural numbers: a(4) = (first term + last term)*n 
               = (10+15)*3 = (25)*3 = 75; a(5) = (17+24)*4 = (41)4 = 164; ...
%C A048395 Also (X*Y*Z)/(X+Y+Z) of primitive Pythagorean triples (X,Y,Z=Y+1) as 
               described in A046092 and A001844. - Lambert Herrgesell (zero815(AT)googlemail.com), 
               Dec 13 2005
%H A048395 <a href="Sindx_Su.html#ssq">Index entries for sequences related to sums 
               of squares</a>
%F A048395 a(n) = 2*n^3 + 2*n^2 + n.
%F A048395 sum ((n+j+2)^2-j^2+1,j=0..n). - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Sep 13 2006
%F A048395 O.g.f.: x(x+5)(1+x)/(1-x)^4. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), 
               Jun 12 2008
%e A048395 Between 3^2 and 4^2 we have 10+11+12+13+14+15 which is 75 or a(4).
%o A048395 (PARI) v0=[1,0,1];M=[1, 2, 2; -2, -1, -2; 2, 2, 3];g(v)=v[1]*v[2]*v[3]/
               (v[1]+v[2]+v[3]); a(n)=g(v0*M^n); for(i=0,50,print1(a(i)," ")) (Herrgesell)
%Y A048395 Cf. A048396, A048397, A000027.
%Y A048395 Cf. A048396, A048397, A000027, A046092, A001844.
%Y A048395 Sequence in context: A049738 A042883 A139273 this_sequence A081886 A081530 
               A145013
%Y A048395 Adjacent sequences: A048392 A048393 A048394 this_sequence A048396 A048397 
               A048398
%K A048395 nonn,nice
%O A048395 0,2
%A A048395 Patrick De Geest (pdg(AT)worldofnumbers.com), Mar 15 1999.

    
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Last modified December 5 23:38 EST 2009. Contains 170428 sequences.


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