A036921 Numbers n such that digit sum of n equals digit sum of 'juxtaposition' and 'sum' of its prime factors (counted with multiplicity).

4, 22, 27, 94, 121, 166, 202, 265, 274, 346, 355, 382, 438, 454, 517, 526, 562, 634, 706, 852, 913, 915, 922, 1086, 1111, 1165, 1219, 1255, 1282, 1507, 1626, 1633, 1642, 1822, 1894, 1903, 1966, 2067, 2155, 2173, 2182, 2227, 2265, 2326, 2362, 2409, 2434

Offset

1,1

Links

Table of n, a(n) for n=1..47.

Mathematica

d[n_]:=IntegerDigits[n]; co[n_, k_]:=Nest[Flatten[d[{#, n}]]&, n, k-1]; t={}; Do[If[!PrimeQ[n]&&Total[d[n]]==Total[d[Total[Times@@@(x=FactorInteger[n])]]]==Total[Flatten[d[co@@@x]]], AppendTo[t, n]], {n, 4, 2435}]; t (* Jayanta Basu, Jun 04 2013 *)

Crossrefs

Cf. A006753, A036920, A019506.

Sequence in context: A098836 A204341 A036920 * A083510 A277586 A078647

Adjacent sequences: A036918 A036919 A036920 * A036922 A036923 A036924

Keyword

nonn,base

Author

Patrick De Geest, Jan 04 1999

Status

approved