A368407 a(n) is the least start of a run of exactly n consecutive integers with an odd number of Fermi-Dirac factors (A064547).
7, 16, 23, 2, 101, 135, 429, 227, 5018, 2682, 1692, 819, 184170, 175683, 93597, 117032, 300773, 466065, 2012413, 2177318, 10267248, 39069334, 25085909, 3829812, 132899228, 316564239, 391031618, 53858226, 355227517, 1484451701, 18503618566, 370565617, 52188004547, 5708850192
Offset: 1
Programs
-
Mathematica
q[n_] := OddQ[Sum[DigitCount[e, 2, 1], {e, FactorInteger[n][[;;, 2]]}]]; q[1] = False; seq[len_] := Module[{s = Table[0, {len}], n = 1, count = 0, n1, d}, While[count < len, n1 = n; If[q[n], While[q[++n1]]; d = n1 - n; If[d <= len && s[[d]] == 0, count++; s[[d]] = n]]; n = n1 + 1]; s]; seq[16] -
PARI
is(n) = {my(e = factor(n)[, 2]); sum(i = 1, #e, hammingweight(e[i])) % 2;} lista(len) = {my(s = vector(len), n = 1, count = 0, n1, d); while(count < len, n1 = n; if(is(n), n1++; while(is(n1), n1++); d = n1 - n; if(d <= len && s[d] == 0, count++; s[d] = n)); n = n1 + 1); s};