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A073170
a(1) = a(2) = 0; for n>2, a(n) = prime(n-1)-n+1.
2
0, 0, 1, 2, 3, 6, 7, 10, 11, 14, 19, 20, 25, 28, 29, 32, 37, 42, 43, 48, 51, 52, 57, 60, 65, 72, 75, 76, 79, 80, 83, 96, 99, 104, 105, 114, 115, 120, 125, 128, 133, 138, 139, 148, 149, 152, 153, 164, 175, 178, 179, 182, 187, 188, 197, 202, 207, 212, 213, 218, 221
OFFSET
1,4
COMMENTS
Smallest x such that A002808(x)-x (cf. A073169) equals n, or 0 if no such value exists.
FORMULA
a(n)=Min{x; composite[x]-x=n}
MATHEMATICA
f[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] t=Table[0, {100}]; Do[s=f[n]-n; If[s<101&&t[[s]]==0, t[[s]]=n], {n, 1, 10000}]; t
Join[{0, 0}, Table[Prime[n-1]-n+1, {n, 3, 70}]] (* Harvey P. Dale, Dec 18 2012 *)
CROSSREFS
Cf. A002808, A073168, A073169. Essentially same sequence as A014689.
Sequence in context: A190670 A226115 A359503 * A014689 A117206 A026443
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 19 2002
EXTENSIONS
Simpler description from Vladeta Jovovic, Mar 29 2003
Definition corrected by Harvey P. Dale, Dec 18 2012
STATUS
approved