A156672 -id:A156672 - cp's OEIS frontend

A156850 a(1)=2, a(n+1) is the smallest prime > (a(n) + sum of digits of a(n)).

2, 5, 11, 17, 29, 41, 47, 59, 79, 97, 127, 139, 157, 173, 191, 211, 223, 233, 251, 263, 277, 307, 331, 347, 367, 389, 419, 439, 457, 479, 503, 521, 541, 557, 577, 599, 631, 643, 659, 683, 701, 719, 739, 761, 787, 811, 823, 839, 863, 881, 907, 929, 953, 971

Offset: 1

Juri-Stepan Gerasimov, Feb 17 2009

			2, 5(>4=2+2), 11(>10=5+5), 17(>13=11+1+1), 29(>25=17+1+7), etc.

Cf. A000040, A156672.

A007953 := proc(n) add(d,d=convert(n,base,10)) ; end: A156850 := proc(n) option remember; if n = 1 then 2; else procname(n-1)+A007953(procname(n-1)) ; nextprime(%) ; fi; end: seq(A156850(n),n=1..120) ; # R. J. Mathar, Feb 20 2009

NestList[NextPrime[#+Total[IntegerDigits[#]]]&,2,60] (* Harvey P. Dale, Aug 21 2011 *)

Definition clarified by Harvey P. Dale, Aug 21 2011

A156768 a(1)=2, a(n+1) is the smallest prime > n + smallest digit of n-th prime*smallest digit of n.

Original entry on oeis.org

2, 5, 11, 19, 37, 11, 13, 17, 17, 29, 11, 13, 17, 17, 19, 23, 23, 23, 23, 29, 23, 29, 37, 31, 41, 41, 29, 29, 29, 31, 31, 37, 37, 37, 41, 41, 41, 41, 43, 43, 41, 43, 47, 47, 53, 53, 53, 53, 59, 59, 53, 59, 59, 59, 59, 67, 67, 71, 67, 71, 61, 67, 67, 67, 71, 71, 73, 79, 89, 89

Offset: 1

Juri-Stepan Gerasimov, Feb 15 2009

			2, 3(=3=1+2*1), 11(>8=2+3*2), 7(=7=3+1*4), 37(>32=4+7*4), etc.

Cf. A000040, A156672.

Corrected by R. J. Mathar, Feb 26 2009

cp's OEIS Frontend

A156850 a(1)=2, a(n+1) is the smallest prime > (a(n) + sum of digits of a(n)).

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