A028836 -id:A028836 - cp's OEIS frontend

A028838 Numbers whose sum of digits is a power of 2.

1, 2, 4, 8, 10, 11, 13, 17, 20, 22, 26, 31, 35, 40, 44, 53, 62, 71, 79, 80, 88, 97, 100, 101, 103, 107, 110, 112, 116, 121, 125, 130, 134, 143, 152, 161, 169, 170, 178, 187, 196, 200, 202, 206, 211, 215, 220, 224, 233, 242, 251, 259, 260, 268, 277, 286, 295, 301, 305, 310, 314, 323, 332, 341

Offset: 1

N. J. A. Sloane

Marius A. Burtea, Table of n, a(n) for n = 1..10535

Cf. A007953, A028836, A028846.

[1] cat [k: k in [2..341] | PrimeDivisors(&+Intseq(k)) eq [2] or &+Intseq(k) eq 1]; // Marius A. Burtea, Jun 11 2019

Select[Range[400],IntegerQ[Log2[Total[IntegerDigits[#]]]]&] (* Harvey P. Dale, Jul 22 2023 *)

ispp(n) = (n==1) || (isprimepower(n, &p) && (p==2));
isok(n) = ispp(sumdigits(n)); \\ Michel Marcus, Jun 11 2019

More terms from Scott Lindhurst (ScottL(AT)alumni.princeton.edu)

Checked by Neven Juric (neven.juric(AT)apis-it.hr), Feb 04 2008

A028889 Numbers whose iterated product of digits is a power of 2.

Original entry on oeis.org

1, 2, 4, 8, 11, 12, 14, 18, 21, 22, 24, 26, 27, 29, 34, 36, 37, 38, 39, 41, 42, 43, 46, 49, 62, 63, 64, 66, 67, 72, 73, 76, 77, 79, 81, 83, 88, 89, 92, 93, 94, 97, 98, 99, 111, 112, 114, 118, 121, 122, 124, 126, 127, 129, 134, 136, 137, 138, 139, 141, 142, 143, 146, 149, 162, 163, 164, 166, 167

Offset: 1

N. J. A. Sloane

			38 -> 3*8 = 24 -> 2*4 = 8 = 2^3.

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Cf. A031347, A028846, A028836.

p2Q[n_]:=IntegerQ[Log[2,NestWhile[Times@@IntegerDigits[#]&,n,#>9&]]]; Select[ Range[200],p2Q] (* Harvey P. Dale, Sep 19 2019 *)

Extended (and corrected) by Scott Lindhurst (ScottL(AT)alumni.princeton.edu)

cp's OEIS Frontend

A028838 Numbers whose sum of digits is a power of 2.

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