A361420 a(n) is the unique number m such that A126168(m) = A361419(n).

1, 6, 8, 15, 21, 52, 58, 82, 106, 118, 268, 158, 356, 1264, 1296, 388, 202, 214, 226, 130, 508, 524, 1936, 160, 138, 298, 692, 2608, 358, 3088, 288, 446, 454, 466, 932, 478, 432, 348, 1792, 538, 562, 578, 586, 12032, 1268, 748, 20736, 1348, 694, 706, 26368, 544, 758

Offset: 1

Author

Amiram Eldar, Mar 11 2023

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A126168, A361419.

Similar sequences: A357313, A357325.

Programs

Mathematica

f[p_, e_] := Module[{b = IntegerDigits[e, 2]}, m = Length[b]; Product[If[b[[j]] > 0, 1 + p^(2^(m - j)), 1], {j, 1, m}]]; is[1] = 0; is[n_] := Times @@ f @@@ FactorInteger[n] - n;
seq[max_] := Module[{v = s = Table[0, {max}], i}, Do[i = is[k] + 1; If[i <= max, v[[i]]++; s[[i]] = k], {k, 1, max^2}]; s[[Position[v, 1] // Flatten]]];
seq[500]

PARI

s(n) = {my(f = factor(n), b); prod(i=1, #f~, b = binary(f[i, 2]); prod(k=1, #b, if(b[k], f[i, 1]^(2^(#b-k)) + 1, 1))) - n; }
lista(nmax) = {my(v = w = vector(nmax+1)); for(k=1, nmax^2, i = s(k) + 1; if(i <= nmax+1, v[i] += 1; w[i] = k)); for(i = 1, nmax+1, if(v[i] == 1, print1(w[i], ", "))); }

Formula

A126168(a(n)) = A361419(n).