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A270359
Positive integer averages of first n Pell numbers; Sum{k=0..n-1} A000129(k) / n where n is in A270342.
0
1, 2, 4, 17, 36, 369, 1820, 20808, 47280, 246561, 6919153, 16008300, 1086517900, 5924129729, 13855173264, 982740019940, 30127233316440, 167427203210673, 5203545562472737, 12300752138736600, 913640750713307860, 162500024938034177361
OFFSET
1,2
EXAMPLE
17 is a term because (0 + 1 + 2 + 5 + 12 + 29 + 70) / 7 = 119 / 7 = 17.
PROG
(PARI) a048739(n) = local(w=quadgen(8)); -1/2+(3/4+1/2*w)*(1+w)^n+(3/4-1/2*w)*(1-w)^n;
for(n=1, 1e2, if(a048739(n-1) % (n+1) == 0, print1(a048739(n-1) / (n+1) , ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Altug Alkan, Mar 15 2016
STATUS
approved