_Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), _, Sep 14 2007

<a href="/Sindx_index/Per.html#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

Klaus Brockhaus, <a href="/A132949/b132949.txt">Table of n, a(n) for n = 1..10000</a>

<a href="/Sindx_Per.html#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

nonn,new

nonn

K. Klaus Brockhaus, <a href="b132949.txt">Table of n, a(n) for n = 1..10000</a>

nonn,new

nonn

K. Brockhaus, <a href="http://www.research.att.com/~njas/sequences/b132949.txt">Table of n, a(n) for n = 1..10000</a>

<a href="http://www.research.att.com/~njas/sequences/Sindx_Per.html#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

nonn,new

nonn

Inverse permutation to sequence A132948.

1, 2, 4, 3, 5, 6, 10, 7, 8, 11, 9, 12, 16, 14, 18, 25, 27, 21, 43, 13, 31, 19, 15, 44, 26, 22, 29, 30, 17, 36, 64, 55, 46, 33, 20, 42, 35, 50, 37, 53, 23, 47, 40, 24, 58, 34, 61, 68, 45, 54, 63, 65, 28, 38, 67, 60, 88, 51, 127, 82, 73, 74, 75, 87, 32, 78, 57, 80, 59, 94, 104, 84

1,2

K. Brockhaus, <a href="http://www.research.att.com/~njas/sequences/b132949.txt">Table of n, a(n) for n = 1..10000</a>

<a href="http://www.research.att.com/~njas/sequences/Sindx_Per.html#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

A132948(10) = 7, hence a(7) = 10; A132948(13) = 20, hence a(20) = 13.

(PARI) {m=130; v=vector(m); w=vectorsmall(4*m); for(n=1, m, k=1; while(w[k]||(prime(n)-1)%k>0, k++); v[n]=k; w[k]=1); u=vector(m); for(j=1, m, a=v[j]; if(0<a&&a<=m, u[a]=j)); j=1; while(j<=m&&u[j]>0, print1(u[j], ", "); j++)}

Cf. A132948.

nonn

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Sep 14 2007

approved