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A351457
a(n) = A351456(n) - A339905(n).
3
0, -1, -2, 8, -5, -6, -8, -4, 14, -11, -6, 8, -12, -18, -22, 84, -14, -2, -20, -12, -36, -18, -20, -24, 0, -28, -40, -16, -29, -46, -18, 40, -36, -32, -58, 296, -28, -42, -56, -44, -32, -76, -44, 24, -66, -48, -44, 136, 8, -36, -64, -16, -50, -104, -66, -72, -84, -59, -30, -72, -50, -54, -100, 1028, -92, -84, -66
OFFSET
1,3
FORMULA
a(n) = A351445(A003961(n)) = A351456(n) - A339905(n).
PROG
(PARI)
A339905(n) = if(1==n, n, my(f=factor(n)); for(i=1, #f~, f[i, 1] = nextprime(1+f[i, 1])-1); factorback(f));
A003958(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1]--); factorback(f); };
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A351456(n) = A003958(sigma(A003961(n)));
A351457(n) = (A351456(n) - A339905(n));
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 12 2022
STATUS
approved