A182011 a(n) is the smallest number k such that the difference between the greatest prime divisor of k and the sum of the other distinct prime divisors equals n.

6, 2, 3, 21, 5, 55, 7, 33, 22, 39, 11, 85, 13, 51, 34, 57, 17, 115, 19, 69, 46, 203, 23, 145, 1295, 87, 58, 93, 29, 259, 31, 185, 615, 111, 74, 205, 37, 123, 82, 129, 41, 235, 43, 141, 94, 371, 47, 265, 1239, 159, 106, 413, 53, 295, 2345, 177, 118, 183, 59, 469

Offset

1,1

Comments

a(n) = n if n is prime.

Links

Alois P. Heinz, Table of n, a(n) for n = 1..1000

Example

a(1) = 6 because 6 = 2*3 and 3 - 2 = 1.

Mathematica

dgpd[n_]:=With[{fi=FactorInteger[n][[;; , 1]]}, fi[[-1]]-Total[Most[fi]]]; Join[{6}, With[{tbl=Table[ {n, dgpd[n]}, {n, 2500}]}, Table[SelectFirst[tbl, #[[2]]==k&], {k, 2, 60}]][[;; , 1]]] (* Harvey P. Dale, Jul 29 2024 *)

Crossrefs

Cf. A001221.

Sequence in context: A201280 A248274 A267568 * A086048 A239578 A248273

Adjacent sequences: A182008 A182009 A182010 * A182012 A182013 A182014

Keyword

nonn

Author

Michel Lagneau, Apr 09 2012

Status

approved