A291766 Restricted growth sequence transform of A291755; filter combining multiplicative order of 2 mod 2n+1 & eulerphi(2n+1) (A002326 & A037225).

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 10, 14, 15, 16, 17, 18, 17, 19, 20, 17, 21, 22, 23, 24, 19, 25, 26, 27, 28, 29, 30, 31, 32, 33, 19, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 34, 45, 46, 29, 47, 48, 43, 49, 50, 41, 51, 52, 53, 45, 54, 55, 56, 57, 43, 58, 59, 60, 61, 49, 62, 63, 64, 51, 65, 66, 67, 68, 69, 53, 70, 71, 57, 72, 61, 73, 74, 75, 61

Offset: 0

Author

Antti Karttunen, Oct 02 2017

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 0..32768

Crossrefs

Cf. A000010, A002326, A037225, A291755.

Cf. A291769, A292267 for related filters.

Cf. A037226, A053006.

Programs

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])); }
A002326(n) = if(n<0, 0, znorder(Mod(2, 2*n+1))); \\ This function from Michael Somos, Mar 31 2005
A291755(n) = (1/2)*(2 + ((A002326(n)+eulerphi(n+n+1))^2) - A002326(n) - 3*eulerphi(n+n+1));
write_to_bfile(0,rgs_transform(vector(32769,n,A291755(n-1))),"b291766_upto32768.txt");