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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.
3
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
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
KEYWORD
nonn
AUTHOR
Michel Lagneau, Apr 09 2012
STATUS
approved