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%I #3 Jul 12 2012 00:39:50
%S 0,0,6,3,30,27,162,171,885,987,4839,5502,26436,30216
%N Number of integers i in range [A000302(n-1)..A024036(n)] of permutation A163355/A163356 with A163915(i)=i, but not A163355(i)=i.
%o (MIT Scheme:)
%o (define (A163913 n) (let ((rp (range-of-n-th-quaternary-forest n))) (let loop ((s 0) (i (car rp))) (cond ((> i (cdr rp)) s) ((and (not (= (A163355 i) i)) (= (A163915 i) i)) (loop (1+ s) (1+ i))) (else (loop s (1+ i)))))))
%o (define (range-of-n-th-quaternary-forest n) (if (zero? n) (cons n n) (cons (A000302 (-1+ n)) (+ (A000302 (-1+ n)) (-1+ (A002001 n))))))
%Y a(n) = 3*A163914(n). See also A163903.
%K nonn
%O 0,3
%A _Antti Karttunen_, Sep 19 2009
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