cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A297106 Xor-Moebius transform of A156552.

Original entry on oeis.org

0, 1, 2, 2, 4, 6, 8, 4, 4, 12, 16, 12, 32, 24, 12, 8, 64, 12, 128, 24, 24, 48, 256, 24, 8, 96, 8, 48, 512, 20, 1024, 16, 48, 192, 24, 24, 2048, 384, 96, 48, 4096, 40, 8192, 96, 24, 768, 16384, 48, 16, 24, 192, 192, 32768, 24, 48, 96, 384, 1536, 65536, 40, 131072, 3072, 48, 32, 96, 80, 262144, 384, 768, 40, 524288, 48
Offset: 1

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Author

Antti Karttunen, Dec 25 2017

Keywords

Comments

Unique sequence satisfying SumXOR_{d divides n} a(d) = A156552(n) for all n > 0, where SumXOR is the analog of summation under the binary XOR operation. See A295901 for a list of some of the properties of the Xor-Moebius transform.
The ordinary Möbius transform of A156552 is given in A297112.
It seems that A091629 gives the fixed points of this sequence.

Crossrefs

Programs

  • 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))));
    A297106(n) = { my(v=0); fordiv(n, d, if(issquarefree(n/d), v=bitxor(v, A156552(d)))); (v); } \\ after code in A295901.