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A324104
a(1) = 0; for n > 1, a(n) = A000010(A156552(n)).
9
0, 1, 1, 2, 2, 4, 4, 6, 2, 6, 8, 10, 16, 16, 4, 8, 32, 12, 64, 18, 6, 20, 128, 22, 4, 48, 6, 24, 256, 12, 512, 30, 16, 84, 8, 18, 1024, 256, 20, 24, 2048, 36, 4096, 66, 10, 324, 8192, 46, 8, 20, 48, 130, 16384, 28, 12, 70, 84, 800, 32768, 42, 65536, 1364, 18, 36, 32, 44, 131072, 216, 256, 40, 262144, 40, 524288, 3840, 12, 408, 16, 108
OFFSET
1,4
LINKS
PROG
(PARI)
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A324104(n) = if(1==n, 0, eulerphi(A156552(n)));
CROSSREFS
Cf. also A323243, A324105 (sigma and tau similarly permuted).
Sequence in context: A096197 A097264 A339810 * A278233 A354753 A377225
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 18 2019
STATUS
approved