A291764 Restricted growth sequence transform of A291784, (psi(n) + phi(n))/2.

1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 9, 10, 11, 12, 13, 13, 14, 15, 16, 17, 17, 18, 18, 19, 20, 21, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 24, 33, 34, 35, 36, 37, 38, 39, 39, 40, 41, 42, 43, 35, 44, 45, 40, 46, 47, 48, 48, 49, 50, 45, 51, 52, 51, 53, 54, 55, 55, 56, 57, 56, 58, 59, 49, 60, 60, 61, 62, 63, 64, 65, 65, 66, 67, 68, 63, 69, 70, 71, 69, 72, 72

Offset

1,2

Links

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

Prog

(PARI)
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; };
write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
A291784(n) = (eulerphi(n)+n*sumdivmult(n, d, issquarefree(d)/d))\2; \\ This function from M. F. Hasler
write_to_bfile(1, rgs_transform(vector(65537, n, A291784(n))), "b291764_upto65537.txt");

Crossrefs

Cf. A000010, A001615, A291784.

Sequence in context: A371156 A176842 A278055 * A319681 A340767 A099848

Adjacent sequences: A291761 A291762 A291763 * A291765 A291766 A291767

Keyword

nonn

Author

Antti Karttunen, Sep 10 2017

Status

approved