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A295886
Filter-sequence combining A003557(n) and A023900(n).
7
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 21, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 34, 38, 39, 13, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 54, 71, 72, 73, 67, 74, 75, 76, 52, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 73
OFFSET
1,2
COMMENTS
For all i, j: a(i) = a(j) => A295887(i) = A295887(j).
LINKS
FORMULA
Restricted growth sequence transform of sequence a(n) = (1/2)*(2 + ((A003557(n) + A295876(n))^2) - A003557(n) - 3*A295876(n)).
PROG
(PARI)
allocatemem(2^30);
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; };
write_to_bfile(start_offset, vec, bfilename) = { for(n=1, length(vec), write(bfilename, (n+start_offset)-1, " ", vec[n])); }
A003557(n) = { my(f=factor(n)); for (i=1, #f~, f[i, 2] = max(0, f[i, 2]-1)); factorback(f); };
A023900(n) = sumdivmult(n, d, d*moebius(d)); \\ This function from Charles R Greathouse IV, Sep 09 2014
v295876 = rgs_transform(vector(up_to, n, A023900(n)))
A295876(n) = v295876[n];
Anotsubmitted6(n) = (1/2)*(2 + ((A003557(n)+A295876(n))^2) - A003557(n) - 3*A295876(n));
write_to_bfile(1, rgs_transform(vector(up_to, n, Anotsubmitted6(n))), "b295886.txt");
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 03 2017
STATUS
approved