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A102070 Numbers that can be expressed as p+p^n (p prime, n >= 0) in more than one way. 1
4, 6, 10, 12, 14, 18, 30, 34, 38, 62, 74, 84, 130, 132, 158, 182, 194, 258, 278, 314, 350, 380, 398, 422, 458, 514, 542, 614, 662, 674, 734, 758, 878, 992, 998, 1094, 1154, 1202, 1214, 1238, 1322, 1382, 1454, 1622, 1658, 1722, 1754, 1874, 1934, 1994, 2018, 2138 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..52.

EXAMPLE

14 = 7+7^1 = 13+13^0. 130 = 2+2^7 = 5+5^3.

PROG

(PARI) v = vector(20000); count = 0; i = 1; p = 2; while (p < 5000, pow = 1; while (pow < 5000, n = p + pow; count++; v[count] = n; pow *= p); i++; p = prime(i)); w = vector(count, x, v[x]); v = vecsort(w); i = 3; for (j = 2, count, if (v[j] == v[j - 1] && v[j] != v[j - 2], print(v[j])));

CROSSREFS

Sequence in context: A284883 A134333 A114331 * A026402 A036438 A066190

Adjacent sequences:  A102067 A102068 A102069 * A102071 A102072 A102073

KEYWORD

easy,nonn

AUTHOR

David Wasserman, Dec 28 2004

STATUS

approved

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Last modified October 16 15:31 EDT 2019. Contains 328101 sequences. (Running on oeis4.)