A355701 - OEIS

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A355701

a(n) = Product of prime(k+1) where k runs through the exponents of the positions 2^k of the 1-bits in A354169(n).

1, 2, 3, 5, 7, 6, 11, 13, 17, 35, 19, 23, 29, 22, 31, 39, 37, 41, 43, 85, 47, 133, 53, 59, 61, 667, 67, 71, 73, 62, 79, 33, 83, 481, 89, 97, 101, 1763, 103, 107, 109, 235, 113, 119, 127, 1007, 131, 137, 139, 3599, 149, 151, 157, 1541, 163, 2059, 167, 173, 179

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

COMMENTS

Compactification of A354169. Offset matches A354169.

LINKS

Michael De Vlieger, Table of n, a(n) for n = 0..10000

Michael De Vlieger, Annotated plot of prime factors p | a(n) at (n, pi(p)) for n = 0..50.

MATHEMATICA

nn = 58; r = c[_] = 0; m = 1; Array[Set[{a[#], c[#]}, {#, #}] &, 2, 0]; Do[k = SelectFirst[Union@ Map[Total, Rest@ Subsets[2^Reverse[Length[#] - Position[#, 1][[All, 1]]] &@ IntegerDigits[2^(r + 2) - m - 1, 2]]], c[#] == 0 &]; Set[{a[n], c[k]}, {k, n}]; m += a[n]; If[And[IntegerQ[#], # > 0], m -= a[#]] &[n/2]; If[And[EvenQ[k], PrimePowerQ[k], k > 2^r], r++], {n, 2, nn}]; Table[Times @@ Map[Prime, 1 + Length[#] - Position[#, 1][[All, 1]]] &@ IntegerDigits[a[n], 2], {n, 0, nn}] (* Michael De Vlieger, Jul 14 2022 *)

CROSSREFS

Cf. A005117, A090252, A354169.

Sequence in context: A076229 A160102 A338224 * A353955 A318954 A296375

Adjacent sequences: A355698 A355699 A355700 * A355702 A355703 A355704

KEYWORD

nonn

AUTHOR

Michael De Vlieger, Jul 14 2022

STATUS

approved