A364950 - OEIS

A364950

Lexicographically earliest infinite sequence such that a(i) = a(j) => A025480(i) = A025480(j) and A348717(i) = A348717(j) for all i, j >= 1.

1, 2, 3, 4, 2, 5, 3, 6, 4, 7, 2, 8, 9, 10, 11, 12, 13, 14, 15, 16, 7, 17, 2, 18, 19, 20, 21, 22, 23, 24, 3, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 2, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 23, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 13, 62, 63, 64, 14, 65, 66, 67, 15, 68, 69, 70, 34, 71

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Restricted growth sequence transform of the ordered pair [A025480(n), A348717(n)], or equally, of the ordered pair [A003602(1+n), A246277(n)].

For all i, j:

a(i) = a(j) => A364949(i) = A364949(j),

a(i) = a(j) => A364951(i) = A364951(j).

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

PROG

(PARI)

up_to = 65537;

rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };

A025480(n) = (n>>valuation(n*2+2, 2));

A348717(n) = if(1==n, 1, my(f = factor(n), k = primepi(f[1, 1])-1); for (i=1, #f~, f[i, 1] = prime(primepi(f[i, 1])-k)); factorback(f));

Aux364950(n) = [A025480(n), A348717(n)];

v364950 = rgs_transform(vector(up_to, n, Aux364950(n)));

A364950(n) = v364950[n];

CROSSREFS

Cf. A003602, A025480, A246277, A348717, A364949, A364951.

Sequence in context: A182718 A212645 A364951 * A100798 A302785 A319825

Adjacent sequences: A364947 A364948 A364949 * A364951 A364952 A364953

KEYWORD

nonn

AUTHOR

Antti Karttunen, Aug 17 2023

STATUS

approved