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A250248
Permutation of natural numbers: a(1) = 1, a(n) = A246278(a(A055396(n)),A078898(n)).
5
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 27, 22, 23, 24, 25, 26, 21, 28, 29, 30, 31, 32, 45, 34, 35, 36, 37, 38, 33, 40, 41, 42, 43, 44, 81, 46, 47, 48, 49, 50, 75, 52, 53, 54, 125, 56, 63, 58, 59, 60, 61, 62, 39, 64, 55, 66, 67, 68, 135, 70, 71, 72, 103, 74, 51, 76, 77, 78, 79, 80, 99, 82, 83
OFFSET
1,2
FORMULA
a(1) = 1, a(n) = A246278(a(A055396(n)), A078898(n)).
Other identities. For all n >= 1:
a(A005843(n)) = A005843(n). [Fixes even numbers].
a(p_n) = p_{a(n)}, or equally, a(n) = A049084(a(A000040(n))). [Restriction to primes induces the same sequence].
A078442(a(n)) = A078442(n), A049076(a(n)) = A049076(n). [Preserves the "order of primeness of n"].
PROG
(Scheme, with memoizing-macro definec from Antti Karttunen's IntSeq-library)
(definec (A250248 n) (cond ((<= n 1) n) (else (A246278bi (A250248 (A055396 n)) (A078898 n))))) ;; Code for A246278bi given in A246278
CROSSREFS
Inverse: A250247.
Similar permutations: A250250 for even more recursed variant of A249818.
Differs from the "vanilla version" A249818 for the first time at n=73, where a(73) = 108, while A249818(73) = 73.
Sequence in context: A250245 A250249 A249818 * A250246 A250250 A375759
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 17 2014
STATUS
approved