A303779 - OEIS

A303779

Restricted growth sequence transform of A278222(A303775(n)).

1, 2, 3, 2, 3, 2, 4, 5, 6, 5, 3, 2, 7, 4, 7, 4, 6, 2, 4, 7, 4, 8, 4, 9, 10, 7, 11, 7, 3, 2, 11, 7, 4, 12, 13, 7, 4, 6, 5, 3, 8, 7, 11, 7, 14, 15, 8, 5, 4, 10, 8, 4, 12, 7, 8, 7, 8, 7, 13, 9, 15, 9, 13, 9, 13, 2, 16, 9, 4, 13, 9, 4, 17, 9, 4, 13, 7, 18, 13, 7, 4, 13, 9, 19, 15, 8, 4, 17, 9, 8, 7, 8, 9, 13, 15, 13, 7, 11, 7, 3, 11, 7, 12, 13, 7

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

OFFSET

0,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..65537

FORMULA

For all i, j: a(i) = a(j) => A303780(i) = A303780(j).

PROG

(PARI)

\\ Needs also code from A303775:

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

write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }

A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };

A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523

A278222(n) = A046523(A005940(1+n));

write_to_bfile(0, rgs_transform(vector(65538, n, A278222(A303775(n-1)))), "b303779.txt");

CROSSREFS

Cf. A278222, A303775, A303780.

Cf. also A286602, A302795, A304088.

Sequence in context: A322592 A329896 A366262 * A087242 A123556 A284017

Adjacent sequences: A303776 A303777 A303778 * A303780 A303781 A303782

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 06 2018

STATUS

approved