The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A286533 Restricted growth sequence of A278533 (prime-signature of A253563). 3
 1, 2, 3, 2, 4, 5, 3, 2, 6, 7, 7, 5, 4, 5, 3, 2, 8, 9, 10, 7, 9, 11, 7, 5, 6, 7, 7, 5, 4, 5, 3, 2, 12, 13, 14, 9, 14, 15, 10, 7, 13, 15, 15, 11, 9, 11, 7, 5, 8, 9, 10, 7, 9, 11, 7, 5, 6, 7, 7, 5, 4, 5, 3, 2, 16, 17, 18, 13, 19, 20, 14, 9, 18, 21, 21, 15, 14, 15, 10, 7, 17, 20, 21, 15, 20, 22, 15, 11, 13, 15, 15, 11, 9, 11, 7, 5, 12, 13, 14, 9, 14, 15, 10, 7 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Antti Karttunen, Table of n, a(n) for n = 0..65537 PROG (PARI) 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])); } A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ This function from Charles R Greathouse IV, Aug 17 2011 A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1]))); \\ After M. F. Hasler's code for A006530. A253550(n) = if(1==n, 1, (n/prime(A061395(n)))*prime(1+A061395(n))); A253560(n) = if(1==n, 1, (n*prime(A061395(n)))); A253563(n) = if(n<2, (1+n), if(!(n%2), A253560(A253563(n/2)), A253550(A253563((n-1)/2)))); \\ Would be better if memoized! A278533(n) = A046523(A253563(n)); write_to_bfile(0, rgs_transform(vector(65538, n, A278533(n-1))), "b286533.txt"); CROSSREFS Cf. A046523, A253563, A286531, A286535, A286622. Sequence in context: A003976 A252371 A275817 * A172520 A290094 A285904 Adjacent sequences:  A286530 A286531 A286532 * A286534 A286535 A286536 KEYWORD nonn AUTHOR Antti Karttunen, May 17 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 28 17:43 EDT 2020. Contains 337393 sequences. (Running on oeis4.)