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A104419 Numbers n such that n, p[n], p[n]+n, p[n]-n and p[n]*n all are 0-less. 10
1, 2, 3, 4, 5, 6, 8, 12, 13, 16, 19, 21, 24, 25, 31, 32, 35, 36, 43, 44, 45, 46, 47, 49, 51, 52, 53, 57, 58, 59, 61, 62, 67, 69, 72, 77, 83, 84, 85, 91, 94, 99, 115, 116, 118, 125, 129, 133, 142, 146, 162, 166, 167, 168, 188, 192, 194, 195, 196 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..59.

EXAMPLE

n=8 is OK because 8, p[8]=19, 19+8=27, 19-8=11, 19*8=152 all are 0-less; n=7 is not because p[7]-7=17-7=10 is not 0-less.

MATHEMATICA

id[x_]:=IntegerDigits[x]; pr[i_]:=Prime[i]; ra=Range[200]; A104419=Select[ra, Union[id[ # ], id[pr[ # ]], id[pr[ # ]+# ], id[pr[ # ]-# ], id[pr[ # ]*# ]][[1]]!=0&]

CROSSREFS

Sequence in context: A103302 A173288 A134677 * A092232 A060322 A143285

Adjacent sequences:  A104416 A104417 A104418 * A104420 A104421 A104422

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Mar 07 2005

STATUS

approved

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Last modified February 17 12:29 EST 2020. Contains 331996 sequences. (Running on oeis4.)