A338454
Starts of runs of 4 consecutive numbers with the same total binary weight of their divisors (A093653).
Original entry on oeis.org
242, 947767, 1041607, 2545015, 3275463, 8170983, 15720871, 21532430, 23752181, 25135885, 25595913, 27981703, 28226983, 30505142, 30962767, 33364805, 37264493, 49002661, 49766629, 52910454, 53408456, 57917191, 57952016, 58331576, 59230454, 60014053, 60723111, 63378005
Offset: 1
242 is a term since A093653(242) = A093653(243) = A093653(244) = A093653(245) = 18.
-
f[n_] := DivisorSum[n, DigitCount[#, 2, 1] &]; s = {}; m = 4; fs = f /@ Range[m]; Do[If[Equal @@ fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 10^7}]; s
A338515
Starts of runs of 3 consecutive numbers that are divisible by the total binary weight of their divisors (A093653).
Original entry on oeis.org
1, 348515, 8612344, 29638764, 30625110, 32039808, 32130600, 32481682, 43664313, 55318282, 55503719, 59671714, 69254000, 73152296, 93470904, 100366594, 103640097, 105026790, 109038462, 109212287, 122519464, 126667271, 147208982, 162007166, 169237545, 173392238
Offset: 1
1 is a term since 1, 2 and 3 are terms of A093705.
-
divQ[n_] := Divisible[n, DivisorSum[n, DigitCount[#, 2, 1] &]]; div = divQ /@ Range[3]; Reap[Do[If[And @@ div, Sow[k - 3]]; div = Join[Rest[div], {divQ[k]}], {k, 4, 10^7}]][[2, 1]]
A338455
Starts of runs of 5 consecutive numbers with the same total binary weight of their divisors (A093653).
Original entry on oeis.org
1307029927, 2116078861, 2665774183, 2809370965, 4108623302, 4493733751, 5333670902, 5497285284, 5679049670, 8209799382, 9665369455, 9708528486, 10353426151, 10606564910, 12777118615, 12795699493, 13660293367, 13847206214, 14351020663, 15735895813, 17912257013
Offset: 1
1307029927 is a term since A093653(1307029927) = A093653(1307029928) = A093653(1307029929) = A093653(1307029930) = A093653(1307029931) = 72.
-
f[n_] := DivisorSum[n, DigitCount[#, 2, 1] &]; s = {}; m = 5; fs = f /@ Range[m]; Do[If[Equal @@ fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 10^7}]; s
A339551
Starts of runs of 3 consecutive numbers with the same product of the binary weights of their divisors (A339549).
Original entry on oeis.org
513059433, 3007912105, 4791685641, 11555664153, 44615854297, 111890605585, 121111724905, 163901238153
Offset: 1
513059433 is a term since A339549(513059433) = A339549(513059434) = A339549(513059435) = 1166400.
-
f[n_] := Times @@ (DigitCount[#, 2, 1] & /@ Divisors[n]); s = {}; m = 3; fs = f /@ Range[m]; Do[If[Equal @@ fs, AppendTo[s, n - m]]; fs = Rest @ AppendTo[fs, f[n]], {n, m + 1, 5*10^9}]; s
Showing 1-4 of 4 results.
Comments