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Integers that reach the (448, 127, 128, 255, 144, 403) cycle described in A234534, after iterations of numerator(sigma(n)/n) = A017665(n).
3

%I #5 Nov 03 2014 10:47:12

%S 16,19,20,21,25,26,31,32,33,35,36,41,42,43,44,45,46,47,48,49,50,52,53,

%T 54,57,58,61,62,63,64,67,68,69,73,74,76,77,79,80,82,88,91,92,93,96,97,

%U 98,99,100,101,102,103,104,105,112,115,116,119,122,125,126

%N Integers that reach the (448, 127, 128, 255, 144, 403) cycle described in A234534, after iterations of numerator(sigma(n)/n) = A017665(n).

%o (PARI) finalc(x, v) = {while (!vecsearch(v, x), x = numerator(sigma(x)/x)); x;}

%o lista(nn, targ=127) = {v = [8, 127, 512, 29127]; for (i=2, nn, if (finalc(i, v) == targ, print1(i, ", ")););}

%Y Cf. A017665, A234534, A249611, A249613, A249614.

%K nonn

%O 1,1

%A _Michel Marcus_, Nov 02 2014