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A324870
a(n) = A324863(n) - A252464(n).
5
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
1
COMMENTS
Question: Are there any other terms than 0's and 1's ? There are only 201 nonzero values among the first 10000 terms and they are all 1's.
A324871 gives the numbers n where a(n) <> 0. The first such number which is not a square is 187 = 11*17.
FORMULA
a(n) = A324863(n) - A252464(n).
PROG
(PARI)
A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1])));
A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A252464(n) = if(1==n, 0, (bigomega(n) + A061395(n) - 1));
A324866(n) = { my(k=A156552(n)); bitor(k, (A323243(n)-k)); }; \\ Needs also code from A323243.
A324863(n) = #binary(A324866(n));
A324870(n) = (A324863(n) - A252464(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 21 2019
STATUS
approved