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A245819
Permutation of natural numbers induced when A245703 is restricted to nonprime numbers: a(n) = 1+A091245(A245703(A018252(n))).
4
1, 2, 3, 4, 5, 8, 6, 12, 7, 9, 13, 26, 10, 14, 18, 11, 15, 48, 19, 20, 35, 16, 21, 32, 25, 17, 22, 63, 27, 56, 28, 138, 46, 23, 29, 43, 34, 38, 24, 30, 80, 60, 36, 88, 72, 37, 167, 42, 59, 31, 39, 55, 45, 62, 50, 33, 40, 100, 77, 320, 47, 92, 109, 90, 49, 201, 54, 98, 76, 41, 51
OFFSET
1,2
FORMULA
a(1) = 1, and for n > 1, a(n) = 1 + A245703(n-1).
a(n) = 1+A091245(A245703(A018252(n))). [Induced when A245703 is restricted to nonprime numbers].
a(n) = 1+A091226(A245703(A008578(n))). [Induced also when A245703 is restricted to noncomposite numbers].
As a composition of related permutations:
a(n) = A245814(A245815(n)).
PROG
(PARI)
A245819(n) = if(1==n, 1, 1 + A245703(n-1));
for(n=1, 10001, write("b245819.txt", n, " ", A245819(n))); \\ The rest of code can be found in A245703.
(Scheme, three different implementations)
(define (A245819 n) (if (<= n 1) n (+ 1 (A245703 (- n 1)))))
(define (A245819 n) (+ 1 (A091245 (A245703 (A018252 n)))))
(define (A245819 n) (+ 1 (A091226 (A245703 (A008578 n)))))
CROSSREFS
Inverse: A245820.
Related permutations: A245703, A245814, A245815.
Sequence in context: A118462 A219360 A275877 * A207802 A222250 A372318
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 16 2014
STATUS
approved