%I #19 Mar 19 2023 10:38:59
%S 1,2,5,10,24,38,87,172,349,706,1407,2752,5487,11103,22285,44429,88993,
%T 177746,356460,712129,1425163,2849424,5701776,11401709,22804522,
%U 45608572,91219022,182438457,364879209,729757797,1459514883,2919031155,5838065175,11676129412,23352260426
%N Index of 2^n in A359804.
%H Rémy Sigrist, <a href="/A361505/a361505.txt">C++ program</a>
%t nn = 2^20; c[_] = False; q[_] = 1;
%t i = 1; j = 2; c[1] = c[2] = True; u = 3;
%t {1, 2}~Join~Reap[Monitor[Do[
%t (k = q[#]; While[c[k #], k++]; k *= #;
%t While[c[# q[#]], q[#]++]) &[(p = 2;
%t While[Divisible[i j, p], p = NextPrime[p]]; p)];
%t If[IntegerQ@ Log2[k], Sow[n]];
%t Set[{c[k], i, j}, {True, j, k}];
%t If[k == u, While[c[u], u++]], {n, 3, nn}], n]][[-1, -1]] (* _Michael De Vlieger_, Mar 18 2023 *)
%o (C++) See Links section.
%Y Cf. A359804, A361502, A361504.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Mar 18 2023
%E a(26)-a(27) from _Michael De Vlieger_, Mar 19 2023
%E More terms from _Rémy Sigrist_, Mar 19 2023
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