cp's OEIS Frontend

A348762 a(n) = A000265((n-8)*(n+8)).

%I A348762 #17 Dec 06 2021 03:15:21
%S A348762 17,9,57,5,105,33,161,3,225,65,297,21,377,105,465,1,561,153,665,45,
%T A348762 777,209,897,15,1025,273,1161,77,1305,345,1457,3,1617,425,1785,117,
%U A348762 1961,513,2145,35,2337,609,2537,165,2745,713,2961,3,3185,825,3417,221,3657
%N A348762 a(n) = A000265((n-8)*(n+8)).
%C A348762 Shares 495 initial terms with A061049. First difference is A061049(504)=62 vs. a(504)=31.
%F A348762 a(n) = A000265(A098849(n-8)).
%e A348762 a( 9) = A000265(( 9-8)*( 9+8)) = A000265( 17) = 17,
%e A348762 a(10) = A000265((10-8)*(10+8)) = A000265( 36) = 9,
%e A348762 a(11) = A000265((11-8)*(11+8)) = A000265( 57) = 57,
%e A348762 a(12) = A000265((12-8)*(12+8)) = A000265( 80) = 5,
%e A348762 a(13) = A000265((13-8)*(13+8)) = A000265(105) = 105.
%t A348762 a[n_] := (n - 8)*(n + 8)/2^IntegerExponent[(n - 8)*(n + 8), 2]; Array[a, 53, 9] (* _Amiram Eldar_, Nov 22 2021 *)
%o A348762 (Ruby) p (9..27).map { |n| x = (n-8)*(n+8); x /= 2 while x.even?; x }
%o A348762 (PARI) A000265(n) = n >> valuation(n, 2);
%o A348762 a(n) = A000265((n-8)*(n+8));
%o A348762 [a(n)|n<-[9..27]]
%o A348762 (Python)
%o A348762 def A348762(n):
%o A348762     a, b = divmod(n*n-64, 2)
%o A348762     while b == 0:
%o A348762         a, b = divmod(a,2)
%o A348762     return 2*a+b # _Chai Wah Wu_, Dec 05 2021
%Y A348762 Cf. A061049, A069834, A000265, A098849.
%K A348762 nonn
%O A348762 9,1
%A A348762 _Simon Strandgaard_, Oct 31 2021