This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A165607 #2 Mar 31 2012 13:21:19 %S A165607 2,6,8,14,15,18,20,25,32,33,42,43,60,62,69,73,74,79,85,87,90,92,93,98, %T A165607 103,104,123,134,140,141,143,151,158,164,168,175,177,182,183,188,195, %U A165607 216,218,223,224,225,231,235,242,249,265,266,272,275,281,283,284,285 %N A165607 a(n) = (A165608(n)-3)/4. %o A165607 (MIT Scheme with MATCHING-POS macro by AK): (define A165607 (MATCHING-POS 1 0 (lambda (n) (let ((w (A004767 n)) (hp (A005408 n))) (let loop ((i 1) (s 1) (zv 0)) (cond ((< s 0) #f) ((>= i hp) (not (zero? zv))) ((zero? s) (loop (1+ i) (+ s (jacobi-symbol (1+ i) w)) (1+ zv))) (else (loop (1+ i) (+ s (jacobi-symbol (1+ i) w)) zv)))))))) %Y A165607 Set-wise difference of A095274 and A165468. %K A165607 nonn %O A165607 1,1 %A A165607 _Antti Karttunen_, Oct 06 2009