A073867 -id:A073867 - cp's OEIS frontend

A181321 Primes with digital sum 70.

189997999, 199799989, 199898899, 199997899, 199997989, 199998889, 268999999, 269998999, 278989999, 278999989, 279889999, 279988999, 287998999, 287999989, 288998989, 288999889, 288999979, 289699999, 289789999, 289889989

Offset: 1

Zak Seidov, Jan 26 2011

The sequence begins with 8438 9-digit numbers.
Then there are 739572 10-digit numbers.
All terms == 7 (mod 18).

T. D. Noe, Table of n, a(n) for n = 1..8438

Cf. A073867, A111380, A181178, A181182.

Cf. similar sequences listed in A244918.

[p: p in PrimesUpTo(3*10^8) | &+Intseq(p) eq 70]; // Vincenzo Librandi, Jul 09 2014

Select[Prime[Range[3*10^8]], Total[IntegerDigits[#]]==70 &] (* Vincenzo Librandi, Jul 09 2014 *)

# see code in A107579 which can be used to produce this sequence by giving the initial term p = 189997999 (or 8*10**7-1, for digit sum 70). - M. F. Hasler, Mar 16 2022

A111380 Smallest prime whose digital sum is equal to the n-th composite number not congruent to 0 (modulo 3).

Original entry on oeis.org

13, 17, 19, 59, 79, 389, 499, 997, 1889, 1999, 6899, 17989, 8999, 39989, 49999, 98999, 199999, 598999, 599999, 799999, 2998999, 2999999, 4999999, 9899999, 19999999, 29999999, 59999999, 189997999, 389999999, 689899999, 699899999, 998999999

Offset: 1

Stefan Steinerberger, Nov 09 2005

Chai Wah Wu, Table of n, a(n) for n = 1..100

Cf. A073867, A157695.

Edited and extended by Robert G. Wilson v, Nov 10 2005

A073868 a(n) is the smallest composite number with the sum of digits = the n-th prime number.

Original entry on oeis.org

20, 12, 14, 16, 38, 49, 98, 289, 689, 3899, 5899, 19999, 68999, 88999, 299999, 899999, 5999999, 7999999, 49999999, 98999999, 199999999, 889999999, 2999999999, 8999999999, 88999999999, 299999999999, 499999999999, 899999999999

Offset: 1

Amarnath Murthy, Aug 15 2002

Cf. A073867.

More terms from Sascha Kurz, Feb 03 2003

A111397 Composite numbers (modulo 3).

Original entry on oeis.org

1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 1, 2, 0, 1, 0, 2, 0, 1, 2, 0, 2, 0, 1, 0, 2, 0, 1, 0, 1, 2, 0, 1, 0, 1, 2, 0, 1, 0, 2, 0, 1, 2, 0, 2, 0, 1, 0, 2, 0, 1, 2, 0, 2, 0, 1, 0, 1, 2, 0, 1, 0, 1, 2, 0, 1, 2, 0, 2, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 2, 0, 1, 0, 1, 2, 0, 1, 0, 2

Offset: 1

Robert G. Wilson v, Nov 11 2005

nonn

If the terms of this sequence are interpreted as the base-3 expansion of a real number, its value is 0.4124999703972179190135867434954940067125524729635148630103267345... and its continued fraction expansion is 0, 2, 2, 2, 1, 4, 5278, 131, 4, 2, 2, 2, 2, 1, 24, 12, 1, 1, 7, 552, 1, 2, 1, ... with increasing partial quotients 2, 4, 5278, 66292, 274715, 420778, 625399, ...

Cf. A002808, A073867.

Composite[n_] := FixedPoint[n + PrimePi[ # ] + 1 &, n]; Table[ Mod[Composite[n], 3], {n, 105}]

a(n) == A002808(n) (mod 3).

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A181321 Primes with digital sum 70.

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A111380 Smallest prime whose digital sum is equal to the n-th composite number not congruent to 0 (modulo 3).

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A073868 a(n) is the smallest composite number with the sum of digits = the n-th prime number.

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A111397 Composite numbers (modulo 3).

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