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A257120
Position of first occurrence of n in A256918.
5
1, 4, 3, 5, 7, 11, 29, 13, 10, 15, 122, 19, 200, 31, 24, 18, 299, 22, 824, 16, 33, 124, 945, 41, 26, 202, 21, 37, 3093, 45, 7059, 40, 126, 301, 53, 66, 13527, 826, 204, 42, 28658, 36, 40810, 130, 57, 947, 46657, 64, 80, 44, 303, 208, 57449, 49, 133, 38, 828
OFFSET
1,2
COMMENTS
A256918(a(n)) = n and A256918(m) != n for m < a(n);
GCD(A257218(a(n)),A257218(a(n)+1)) = n;
if A257218 is a permutation, then also this sequence is a permutation;
a(n) < A257475(n); a(n) = A257475(n) - A257478(n).
a(n) >= A257122(n)-1. - Ivan Neretin, May 02 2015
LINKS
Hiroaki Yamanouchi, Table of n, a(n) for n = 1..72
EXAMPLE
See A257478.
PROG
(Haskell)
import Data.List (elemIndex); import Data.Maybe (fromJust)
a257120 = (+ 1) . fromJust . (`elemIndex` a256918_list)
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Apr 25 2015
EXTENSIONS
a(41)-a(57) from Hiroaki Yamanouchi, May 03 2015
STATUS
approved