

A277895


a(n) = index of the column where n is located in array A277898, a(2) = 0.


4



0, 1, 2, 1, 3, 1, 4, 2, 5, 1, 3, 1, 4, 5, 6, 1, 6, 1, 7, 8, 7, 1, 8, 2, 9, 10, 11, 1, 9, 1, 10, 3, 12, 4, 13, 1, 14, 15, 11, 1, 12, 1, 5, 6, 13, 1, 16, 2, 17, 7, 18, 1, 14, 8, 15, 9, 3, 1, 10, 1, 11, 12, 19, 4, 16, 1, 13, 14, 17, 1, 18, 1, 20, 21, 15, 5, 22, 1, 16, 17, 23, 1, 18, 19, 24, 25, 19, 1, 26, 6, 20, 2, 21, 7, 20, 1, 21, 22, 27, 1
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OFFSET

2,3


COMMENTS

a(2) = 0 as 2 does not occur in the array A277898 proper.
From a(3) onward the ordinal transform of A277892 from its first nonzero term a(3) onward: 1, 1, 2, 1, 3, 1, 2, 1, 4, 2, 5, 2, 2, 2, 6, 1, 7, 2, ... The relation does not hold the other way, because not all columns of A277898 are monotonic, for example, 16 is located below 18 in the sixth column of that array. Already the array's second column (A277900) is nonmonotonic.


LINKS

Antti Karttunen, Table of n, a(n) for n = 2..10000 (computed from the bfile provided by Hans Havermann for A277892)


FORMULA

a(2)=0, for n >= 3, if A010051(n) = 1 [when n is a prime], a(n) = 1, otherwise a(n) = 1 + a(A277894(n)).


PROG

(Scheme) (definec (A277895 n) (cond ((<= n 2) 0) ((= 1 (A010051 n)) 1) (else (+ 1 (A277895 (A277894 n))))))


CROSSREFS

Cf. A010051, A277892, A277894, A277898, A277900.
Sequence in context: A111902 A316211 A329480 * A328772 A300726 A325352
Adjacent sequences: A277892 A277893 A277894 * A277896 A277897 A277898


KEYWORD

nonn


AUTHOR

Antti Karttunen, Nov 08 2016


STATUS

approved



