A133956 - OEIS

A133956

Complement of A133957.

2, 3, 5, 7, 11, 13, 17, 19, 29, 31, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 239, 251, 263, 269, 281, 293, 307, 349, 401, 409, 419, 421, 431, 433

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OFFSET

1,1

COMMENTS

Home primes whose homeliness is 1.

Number of terms < 10^n: Pi(10^n)- {0, 2, 37, 274, 2087, 15472, 76940, ...}.

LINKS

Table of n, a(n) for n=1..58.

EXAMPLE

Only {2} -> 2, {3} -> 3, etc. Whereas {6 & 23} -> 23 thus 23 has a homeliness of 2 and therefore is not a member of this sequence.

MATHEMATICA

lst = {}; f[n_] := FromDigits@ Flatten[ IntegerDigits@ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger@n, 2]; h[n_] := NestWhileList[f@# &, n, !PrimeQ@# &, 1, 28]; Do[p = h[n][[ -1]]; If[ PrimeQ@p && p < 10^7 && p != n, Print[{n, p}]; AppendTo[lst, p]], {n, 2, 1000}];

Complement[ Prime@ Range@ 100, {23, 37, 211, 223, 227, 229, 233, 241, 257, 271, 277, 283, 311, 313, 317, 331, 337, 347, 353, 359, 367, 373, 379, 383, 389, 397, 523, 541}]

CROSSREFS

Cf. A037274, A118756, A133957, A133958, A133960, A133962, A133964, A133966, A133968, A133970, A133972, A133974, A133976, A133978.

Sequence in context: A104885 A127052 A092570 * A176164 A141409 A238647

Adjacent sequences: A133953 A133954 A133955 * A133957 A133958 A133959

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 30 2007

STATUS

approved